Watt's Up

College of Optical Sciences News for November 6, 2008

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Today's Colloquium:  3:30 p.m.  Meinel 307

Brian DeMarco, University of Illinois, will present Experiments on Dirty Bosons.  Brian Anderson is the host.

Abstract:  Ultra-cold atom gases trapped in an optical lattice are now poised to make strong contributions to resolving outstanding questions in condensed matter physics.  I will talk about how we are using this system to simulate models relevant to dirty superconductors.  I will report on two new results, including the observation of dissipation induced by quantum tunneling and thermal activation of phase slips, and the first experiments on an optical lattice that include fine-grained disorder.

Today's Special Presentation:  9:30 a.m.  Meinel 821

Konstantin L. Vodopyanov, Senior Research Scientist at Stanford University's Ginzton Laboratory, will present New Light From Gallium Arsenide:  Terahertz-Wave Generation From Periodically-Inverted GaAs.  Nasser Peyghambarian is the host.

Abstract:  Gallium arsenide has attracted attention as a nonlinear optical material since the beginning of the laser era, because of its high 2-nd order nonlinearity and superior transparency, both in the mid- and far-infrared.  The main problem was how to achieve phase-matched interaction in this dispersive and optically isotropic material. Now it became possible, using epitaxial and other methods, to create GaAs structures with periodically-flipped orientation, and thus resolve the phase-matching problem. This opened up a variety of new applications in the mid-IR: broadly-tunable optical parametric oscillators, difference frequency and supercontinuum generators and polarization-insensitive frequency converters. The most recent application of periodic GaAs is efficient photonic generation of frequency-tunable THz waves with > 1 mW of output average power. I will talk about latest experiments on photonic THz generation - using optical rectification with fs pulses and cavity-enhanced frequency mixing with ps pulses, as well as their applications.

About the Speaker:  Konstantin Vodopyanov obtained his BS degree from Moscow Institute of Physics and Technology ("Phys-Tech") and accomplished his PhD in 1983 in the Oscillations Lab of Lebedev Physical Institute, led by Nobel Prize winner Alexander Prokhorov. He was an assistant professor at Moscow Phys-Tech (1985-90), Alexander-von-Humboldt Fellow at the University of  Bayreuth, Germany (1990-92), and a Royal Society Fellow and lecturer at Imperial College, London, UK (1992-98). He was awarded a DSc degree (Habilitation) by General Physics Institute, Moscow in 1993. In 1998, he moved to the United States and became head of the laser group at Inrad, Inc., NJ (1998-2000), and later director of mid-IR systems at Picarro, Inc.,CA (2000-2003). In 2003 he returned to Academia and is now with the E.L. Ginzton Lab at Stanford University. K. Vodopyanov is a Fellow of the UK Institute of Physics and a Fellow of the Optical Society of America. He has > 260 technical publications and is member of program committees for several major laser conferences; he was elected Program Chair for CLEO'2008 and General Chair for 2010. His research interests include nonlinear optics, laser spectroscopy, atomic force microscopy with spectral resolution, mid-IR and terahertz-wave generation using micro-and nanostructured materials and applications.

Monday's ACMS Speaker:  10:00 a.m.  Meinel 821

Paolo Di Trapani, Department of Quantum Electronics, Vilnius University, Vilnius, Lithuania and CNISM and Department of Physics and Mathematics, University of Insubria at Como, Italy, will present Controlled X Wave Formation in Bulk Quadratic and Cubic Nonlinear Media. 

Abstract:  X waves emerge as an appropriate tool for describing nonlinear interaction among waves featuring different intesities, extension and phase and/or group velocities, supporting an easy understanding of the impact of pump spatial and temporal characteristic on the generated waves.

Optical Sciences Has Talent!

By Gail Varin.  Do you ever wonder what graduate students do in their spare time?

• Sarmad Albanna: Piano player and composer

• Chris Berger: Wedding photographer www.chrisbergerphoto.com, ballroom dancer,  competes and teaches beginners class, treasurer of Ballroom Dance Club

• Poma Bhowmik: Swing, salsa and ballroom dancing, Bharat Natyam dancing, piano and violin, singing.  http://in.geocities.com/medhahari/bharatnatyam/bharatnatyam.html  

• Amber Czajkowski: Competitive equestrian stadium jumping, riding horses since 5

• Julia Craven: Crafter, enjoys crocheting, knitting, sewing, and quilting

• Erin Ford: Kickboxing http://en.wikipedia.org/wiki/Muay_Thai

• Goldie Gibbons: Trombone player, Old Pueblo British Brass Band

• Boris Glebov: Ballroom dancing club member

• Anael Guilmo: Bass guitar player (available if anyone is looking for a bass player)

• Roland Himmelhuber: Sports climbing play electronic guitar, dog agility and ride snake board. http://en.wikipedia.org/wiki/Snakeboard

• Masaki Hosoda: Kyudo (Japanese archery), child-raising

• Stacie Hvisc: Flute, piccolo and piano player.  Member University of Arizona Philharmonic Orchestra.  Concert is Dec. 5. http://web.cfa.arizona.edu/music/index.php/story?storyid=1493&time=9151

• James Johnson: Ballroom dancing

• Matthew Jungwirth: Play the tenor sax, piano, sing, act, and play the trap set.  http://en.wikipedia.org/wiki/Drum_kit

• Yi-Ying Lai: Clarinet player, abacus and mental arithmetic

• Nathan Lewis: Racquetball, swimming, water polo, wake boarding, windsurfing (looking for other windsurfers), hiking and rock climbing

• Christian Lytle: Road and mountain cycling, canoeing (Boy Scout trip guide), backpacking/hiking, martial arts, juggling and handbell player (played in handbell choir)  http://en.wikipedia.org/wiki/Handbell

• Leonardo Montilla:  Long distance runner, coach high school cross country and track

• Sukumar Murali: Salsa dancing, Arizona Professional League Cricket player and racquet ball

• Tyler Neely: Saxophones and guitar. Bands: Vampyros Bonobos: http://www.myspace.com/vampyrosbonobos ; 8 Minutes to Burn: http://www.myspace.com/8minutestoburn  Recent Shows: Midnight show Thursday 10/23 at the Hut (8m2b) and Halloween Spectacular: Friday 10/31 at the Hut (Vampyros and 8m2b!)

• Hannah Noble: Avid yoga practitioner, and a cooking enthusiast

• JD Olitzky: Pageant singer as a child, cook

• Ryeojin Park: Piano player and cartoonist

• Matt Risi: Singer (Newman Center) and swing dancer “Swing Cats” meets Tuesdays at 7:00 pm in the basement of the Ina Gittings Building

• Adam Roberts:  Swing dance, DJ/instructor, classical guitar player, photographer, blacksmithing

• Katie Schwertz: Piano player, playing since 5 years old

• Robin Seibel: Bicyclist, ice climbing, ex-skydiving instructor, master parachute rigger, BASE jumper (buildings, aerials, spans, earth) and photography

• Chris Summitt:  Photography, teach guitar and make electronic music on the computer. Music website http://www.u.arizona.edu/~crs2/music.html

• Aron Traylor: Ballroom dancing club member

• Pouria Valley: Cello player, Tehran and Arizona Philharmonic Orchestra, soccer

• Corrie Vandervlugt: Competitive dancer and teaches intermediate/advanced ballroom dance classes. http://clubs.arizona.edu/~bdc/Club_Information.html  President Ballroom Dance Club. Club meets Monday, Wednesday and Thursday 8 to 10 pm in the Ina Gittings gym

• Lirong Wang: Dancing and Chinese painting

• Kali Wilson: Baking chocolate cookies, volleyball (blocking)

• Stefano Young:  Salsa dancer, guitar and bass band: Vampyros Bonobos http://www.myspace.com/vampyrosbonobos

• Garam Yun: Salsa dance and tango, plays gayageum, a Korean traditional string instrument.  http://en.wikipedia.org/wiki/Gayageum

• Rene Zehnder: Plays concert zither, a German/Austrian instrument

• Ping Zhou: Plays yangqin, a Chinese hammered dulcimer:  Member Summer Thunder Asian Music Club http://www.melodyofchina.com/06instruments/yangqin.html

Accepting Applications:  The Arthur H. Guenther Congressional Fellowship Program

Deadline for 2009-2010 applications is Friday, January 9, 2009:  OSA and SPIE offer a congressional fellowship program providing members with an invaluable opportunity of public policy learning. Fellows gain a perspective that enhances their industrial, academic or government careers and the optics community’s ability to more effectively communicate with Congress. The Fellowship is an ideal way to spend an academic sabbatical or leave of absence from a company.

A Unique Opportunity:  The Arthur H. Guenther Congressional Fellow works in the office of a U.S. Senator or Representative or with a congressional committee to get first-hand knowledge of congressional operations, contribute to the policymaking process, and forge links among the engineering, scientific, and public policy communities.

Term:  Fellowships are normally for one year, running September through August. The Guenther Fellow will join more than two dozen other scientists and engineers in early September 2008 for an intensive orientation program on the legislative and executive branches. This program is organized by the American Association for the Advancement of Science (AAAS), which also provides educational and collegial programs for the Fellow throughout the year. Following interviews on the Hill, Fellows choose a congressional office – personal or committee staff – where they wish to serve. Fellows are expected to handle varied assignments, both technical and non-technical.

Support:  A stipend of $58,000 is provided by OSA and SPIE, and additional support from other sources, such as a present employer, is permitted. The Societies also provide an allowance for health insurance, travel, and relocation expenses to the Washington, D.C. area. Final selection of the Fellow will be made in March/April 2009 after personal interviews are conducted.

Qualifications:  Fellows are evaluated on the basis of technical competence, responsible work experience, ability to serve in a public environment and evidence of service to OSA, SPIE and the profession. Prospective Fellows must have a Ph.D. or equivalent doctoral level degree by program orientation (September 1, 2009); significant familiarity with optical engineering or science disciplines; a working understanding of the optical engineering and science communities; and demonstrated interest in the United States public policy process. Although prior experience in public policy is not necessary, a demonstrable interest in applying science and engineering to the solution of United States policy issues is required. Federal employees are not eligible. U.S. citizenship is not required; however, applicants must be authorized to work in the United States. Applicants should have excellent interpersonal and communication skills and possess the flexibility to tackle a variety of work. Specifically excluded as selection criteria are age, sex, creed, race, ethnic background, and partisan political affiliation.

Application:  Applications must be postmarked by Friday, January 9, 2009. Candidates should submit the following materials:

• A detailed resume or curriculum vitae providing information about educational background, professional employment and activities, professional publications and presentations, public policy and legislative experience and committee and advisory group appointments

• A statement of approximately 1,000 words addressing the applicant's interest in the fellowship, career goals, contributions the applicant believes he or she can make as an Guenther Fellow to the legislative process and what the applicant wants to learn from the experience

• Three signed letters of reference sent directly to the address below, specifically addressing the applicant's ability to work on Capitol Hill as a special legislative assistant. Letters of reference may be emailed directly to astark@osa.org, but must be in PDF format, on official letterhead and include an electronic or scanned signature.

Application Materials Should be Mailed or Emailed to:
Arthur H. Guenther Congressional Fellowship Program
c/o Angela Stark
Optical Society of America
2010 Massachusetts Ave. NW
Washington, DC 20036
Office: 202.416.1443
Email: astark@osa.org

Note: Applicants applying for both the Arthur H. Guenther and OSA/MRS Congressional Fellowship can send in one set of application materials for both fellowships, as long as it is noted that the materials are for both fellowships.  

Accepting Applications:  The OSA / MRS Congressional Fellowship

Deadline for 2009-2010 applications is Friday, January 9, 2009.  OSA and MRS offer a congressional fellowship program providing members with an invaluable opportunity of public policy learning. Fellows contribute effective use of optical and materials science knowledge in government and broaden awareness of the value of scientist- and engineer-government interaction among our memberships, the federal government, and the public.

Program:  The Fellow spends one year working as a special legislative assistant on the staff of a member of Congress or congressional committee. Activities may involve conducting legislative or oversight work, assisting in congressional hearings and debates and preparing briefs and writing speeches. The Fellow also attends an orientation program administered by the American Association for the Advancement of Science (AAAS) on congressional and executive branch operations, which includes guidance in the congressional placement process, and a year-long seminar series on science and public policy issues. The AAAS also administers many other aspects of the program for the OSA/MRS Fellow, as well as other Fellows sponsored by nearly two dozen other scientific societies.

Criteria:  A prospective Fellow must have a record of success in research or scholarship in a field relevant to optical science and technology and/or materials. The Fellow must also demonstrate sensitivity toward policy issues and have a strong interest in applying scientific and technical knowledge to United States public policy issues. The Fellow must be able to work quickly and communicate effectively on a wide variety of topics and work cooperatively with individuals having diverse viewpoints. An applicant is expected to be a member of OSA or MRS (or an applicant for membership) and have a Ph.D by September 1, 2009. U.S. citizenship is not required; however, applicants must be authorized to work in the United States.

Award:  The Fellow will have a one-year appointment beginning Sept. 1, 2009. The Fellowship stipend will be $58,000, plus additional funds for health insurance, travel and relocation expenses to the Washington, D.C. area.

Application:  Applications must be postmarked by Friday, January 9, 2009. Candidates should submit the following materials:

• A detailed resume or curriculum vitae providing information about educational background, professional employment and activities, professional publications and presentations, public policy and legislative experience and committee and advisory group appointments

• A statement of approximately 1,000 words addressing the applicant's interest in the fellowship, career goals, contributions the applicant believes he or she can make as an OSA/MRS Fellow to the legislative process and what the applicant wants to learn from the experience

• Three signed letters of reference sent directly to the address below, specifically addressing the applicant's ability to work on Capitol Hill as a special legislative assistant. Letters of reference may be emailed directly to astark@osa.org, but must be in PDF format, on official letterhead and include an electronic or scanned signature.

Application Materials Should be Mailed or Emailed to:
OSA/MRS Congressional Science and Engineering Fellow Program
c/o Angela Stark
Optical Society of America
2010 Massachusetts Ave. NW
Washington, DC 20036
Office: 202.416.1443
Email: astark@osa.org

Note: Applicants applying for both the OSA/MRS and Arthur H. Guenther Congressional Fellowship can send in one set of application materials for both fellowships, as long as it is noted that the materials are for both fellowships.

Academic Writing Workshop for International Graduate Students:  December 29 - January 16

Dissertations     Theses     Seminar Papers     Articles for Publication     Grant Writing     Reports

The Academic Writing Workshop (Writing Center, UA English Department) is designed to help International Graduate Students with their academic writing. The workshop is limited to only 12 people, so we can focus on your individual work and writing needs.  The Workshop runs a full three weeks of intensive focus on your writing.  The Academic Writing Workshop focuses on many levels of writing:

• Focus and Clear Arguments (we will analyze and refine thesis statements and supporting evidence).

• The Craft and Style of Writing (we can start to address abstract ideas, such as “flow” and strong sentence formations).

• Grammar and Mechanics (we will focus on what rules you need to know for your writing, applying those rules in class).

• Organization of Ideas (we will look at your road-mapping, your transitions, and how your ideas develop into one another).

• Development and Support (we will consider the audience and what level of information/ description that is best suited to particular purposes).

You receive a tremendous amount of time and attention focused on your writing:

• The Workshop meets Monday, Wednesday, and Friday from 9:00 a.m. to noon in Bear Down Gym, room 220.

• Small groups of two to four students and the instructor also meet twice during the three-week period (time and place determined during the workshop).

• The instructor will also meet with all participants one time after the three-week period (appointments are made during the workshop period) for a final one-on-one conference.

Seats are limited in the Workshop; we are only able to accommodate 12 students for the December 29 – January 16 dates.  The cost of the Academic Writing Workshop is $500 (checks can be made payable to the University of Arizona). Deadline to apply is December 15, 2008.  Mail payment to: Writing Program - Department of English, PO Box 210067, University of Arizona, Tucson AZ 85721-0067 or deliver to Modern Languages 380.   Include your name, address, phone, email and what graduate program you are enrolled in.

If you are interested or have any questions, please contact Anne-Marie Hall at 621-3553 or by email at hall@email.arizona.edu

INTERNATIONAL GRADUATE STUDENT

ACADEMIC WRITING WORKSHOP APPLICATION

NAME________________________________________________________________

ADDRESS_____________________________________________________________

CITY_________________________ STATE__________________ ZIP____________

STUDENT ID NUMBER__________________________________________________

EMAIL ADDRESS_______________________________________________________

PHONE NUMBER________________________________________________________

DEPARTMENT__________________________________________________________

PERSONAL WRITING GOALS FOR THIS WORKSHOP INCLUDE:

PAYMENT:  

CASH___________________

CHECK__________________

DEPARTMENT IDB__________________________________________________

Happy Birthday and Best Wishes for a Wonderful Year

November 18

Kathy Creath (kcreath@u.arizona.edu)
James Johnson (jjohnson@optics.arizona.edu)
Earl Parsons (eparsons@optics.arizona.edu)

November 19

Matthew Bergkoetter (mdb1@email.arizona.edu)
Jiahua Fan (jiahua.fan@ge.com)
J. Scott Tyo (tyo@optics.arizona.edu)

November 21

Palash Gangopadhyay (palash@optics.arizona.edu)
Saleena Lee (saleenal@email.arizona.edu)
Leonardo Montilla (lmontilla@optics.arizona.edu)

November 22

Wai-Sze Lam (waisze@optics.arizona.edu)
Richard Ziolkowski (ziolkowski@ece.arizona.edu

OSC Calendar

November 5 - 7  

Sixth Annual Math, Science, and Technology Funfest.  Tucson Convention Center.

November 7

OSC Sports Friday.  Location and sport are TBA.

November 10

PhD Final Oral.  11:00 a.m.  Radiology 101.  Joshua Udovich will present Confocal Microendoscopy: Characterization of Imaging Bundles, Fluorescent Contrast Agents, and Early Clinical Results.

November 11

Veterans Day.  UA Holiday.  Enjoy the day off.

November 12

PhD Final Oral.  1:00 p.m.  Radiology 101.  Angelique Kano will present Ultrathin Single and Multi-Channel Fiberscopes for Biomedical Imaging.

On Campus

November 6

Aerospace and Mechanical Engineering Seminar.  4:00 p.m.  AME Lecture hall, Room S212. 

Dr. Aditi Chattopadhyay, Arizona State University Department of Mechanical and Aerospace Engineering and Director, Adaptive Intelligent Materials & Systems (AIMS) Center, will present A Multidisciplinary Approach to Structural Health Monitoring and Prognosis of Aerospace Components.

November 7

Physics Colloquium.  2:15 p.m.  PAS 218.  At 2:15 p.m. a graduate student will be the speaker.  At 3:00 p.m. guest speaker, Professor Ruprecht Machleidt will present The Nuclear Force Problem: Is the Never-Ending Story Coming to an End?

November 12

Mathematical Physics Seminar.  1:00 p.m.  Math 402.  Mei Yin, Department of Mathematics, University of Arizona, will present Spectrum of RG Transformations 2.

Optical Research Engineer.  Optical Systems Group.  Blacksburg, Virginia.  Luna Innovations develops and manufactures new-generation products for the healthcare, telecommunications, energy and defense markets.  Our products are used to measure, monitor and improve critical processes in the markets we serve. Through its disciplined commercialization business model, Luna has become a recognized leader in transitioning science to solutions. Luna is headquartered in Roanoke, Virginia.  Due to growth, Luna Innovations is seeking an entry-level Optical Research Engineer to be part of a multidisciplinary team involved in the development of cutting-edge fiber-optic sensing instrumentation and thin film characterization equipment. This key technical position will be responsible for system and subsystem level product design, designing and implementing test plans, and performing applied research in support of advanced fiber-optic technology and system development as well as algorithm development and computer automation of hardware related to thin film characterization equipment.  The successful candidate will be a self-starter, capable of fulfilling complex technical tasks with minimum oversight and supervision. The successful candidate will have strong communication, technical writing, problem solving, and interpersonal skills and function well in a highly dynamic, team oriented environment.  B.S. or M.S. in Electrical Engineering with a focus on optics, or related field.  Self-starter, highly motivated, creative, and enthusiastic.  Strong communication, technical writing, problem solving, and interpersonal skills and functions well in a highly dynamic, team oriented environment.  Strong mathematics background.  Excellent mathematical working knowledge of the following concepts is desirable: Calculus, Fourier Theory, Digital Signal Processing Theory, Matrix Algebra.  Strong electromagnetics background is required.   Working knowledge of MatLab; LabView; and optics is required (either theoretical, applied, or preferably, both).  Technical Expertise Desired:  Working knowledge of C or C++ is desirable.  Knowledge of imaging system design is desirable.  Knowledge of data processing for imaging is desirable.  Digital and analog electronics design experience is desirable.  Working knowledge of device physics behind FBGs, couplers, circulators, polarizers, fiber birefringence, index guiding, and polarization as it relates to fiber-optics is desirable.  Working knowledge of detectors and signal theory, particularly the following: shot noise, thermal noise, quantum efficiency, responsivity, SNR, BER, NEP, and blackbody radiation theory is desirable.  Working knowledge of detector types is desirable, including:  PIN, APD, Si, InGaAs, InP, etc.  Familiarity with concepts such as refraction, diffraction, coherence, polarization, and spontaneous and stimulated emission as they relate to lasing, is desirable.  Familiarity with free-space optics concepts is desirable.  Familiarity with integrated optics concepts is desirable.  Due to the nature of our work in the government contract research area, U.S Citizenship or Permanent Resident status is a firm requirement.  We offer an outstanding compensation package.  Qualified candidates, please email resume to wesself@lunainnovations.com at Luna Innovations, Corporate Headquarters, 1 Riverside Circle, Suite 400, Roanoke, VA  24016.  EOE / AA

Engineering Intern Opening.  SOLON Corporation.  SOLON Corporation is looking to fill two engineering intern positions at its location in Tucson, AZ.  Candidates will have the opportunity to gain real world experience while working for an international company that is a leading provider of solar power plant engineering solutions for large-scale projects.  Who we are:  SOLON Corporation located in Tucson, Arizona is a leading provider of intelligent solar power plant solutions for large-scale projects.  The international SOLON Group is one of the largest solar module manufacturers in Europe, employs more than 850 people worldwide, and has offices and manufacturing in 5 different countries including Germany, Italy and the United States.  Your profile:  Pursuing a degree in Electrical or Optical Engineering, with emphasis on power generation in lieu of digital electronics.  Highly motivated with a proven ability to work independently as well as in a team environment.  Desire to learn about solar technology and the solar industry.  Solar cell technology background helpful.  Excellent written and oral communication skills.  Our offer:  A dynamic and successful company in a quickly growing market.  Interesting tasks with the opportunity to develop own ideas.  Integration into highly committed and cooperative team.  Short lines of communication and lots of space for your own ideas.  Passion and a pioneering spirit. Expertise and experience. We put these things to work to help propel ecological change in the energy market. Would you like to work in a field that focuses on the environment? To be part of a dynamic company that enjoys outstanding success in a high-growth market? Then join us. Work with us to revolutionize the use of solar energy while also achieving your career goals. After all, the future belongs to solar energy – and to those who work for its progress.  Interested?  For further questions regarding the position, please contact Anna Klautsch via E-Mail to aklautsch@solonamerica.com   Please send your application (cover letter, resume, references) via E-Mail to: aklautsch@solonamerica.com

Senior Electro-Optical Engineer.  Lightfleet Corporation.  Background Information:  Lightfleet® Corporation is an emerging Pre-IPO growth company located in a suburb of Portland, OR that is 100% privately funded and employs 50+ people.  Lightfleet has invented and developed a new type of Interconnect technology that lets computers talk to each other using broadcast light. This invention, called Corowave™ technology, makes systems smaller, use less power, and do more work.  The Corowave™ technology is a patented “all-to-all broadcast optical interconnect” that eliminates the congestion and contention that create internal bottlenecks in inter-processor communication that exist because of limitations in today’s point-to-point interconnect technologies.  Customers using systems based on Lightfleet technology will see significant benefits from increased efficiency in computing performance and data throughput, as well as reduced power consumption.  This Interconnect will first be utilized in a new type of server that will be manufactured on-site.  For more information, please visit our website at www.lightfleet.com or our AboutUs page at www.aboutus.org/lightfleet   Lightfleet is actively searching to fill our Sr. Electro-Optical Engineering position. The successful candidate will bring to Lightfleet their expertise in design and development of electro-optical systems. This will include:  Strong background in working with high speed electro-optical devices including transmitters and receivers.  Optical design and modeling of components and systems.  Performing laboratory work entailing (1) test and characterization of high speed electro-optical components and systems (including BER testing, analyzing eye patterns, etc.), (2) test and characterization of passive optical components, (3) alignment of passive and active components, and (4) working with optical metrology tools.  Documenting technical reports, work instructions and engineering drawings.  Requirements:  5+ years commercial experience in design, development, and testing of optical and electro-optical components and systems.  Master’s degree in Electrical, Optical, or Mechanical Engineering (or equivalent).  Experience using commercially available optical design tools (such as Zemax, ASAP, LightTools, Code V, R-Soft, etc.)  Strong experience with design for manufacturability and reliability.  Strong knowledge of geometric and physical optics.  Good understanding of opto-electronic device physics.  Ability to work with mechanical engineers in developing optical platform sub-assemblies / assemblies.  Ability to work both independently and in a group setting.  Current eligibility to work in the US.  Desired qualifications:  Doctorate Degree in Electrical, Optical, or Mechanical Engineering (or equivalent)   Experience working in an early stage company.  Familiarity with LabVIEW.  Have worked on multiple product development cycles from concept through production.  Knowledge of computer architectures (preferred but not required).  Excellent communication skills to be able to work effectively with cross-functional teams.  For More Information:  Please visit our website at www.lightfleet.com or our AboutUs page at www.aboutus.org/lightfleet  To Apply:  If you have the skills and experience required for this position, please submit your resume to careers@lightfleet.com.  Lightfleet Corporation is an equal opportunity employer.

Senior Optical Metrology/Test Engineer.  Lightfleet Corporation.  Lightfleet® Corporation is an emerging Pre-IPO growth company located in a suburb of Portland, OR that is 100% privately funded and employs 50+ people.  Lightfleet has invented and developed a new type of Interconnect technology that lets computers talk to each other using broadcast light. This invention, called Corowave™ technology, makes systems smaller, use less power, and do more work.  The Corowave™ technology is a patented “all-to-all broadcast optical interconnect” that eliminates the congestion and contention that create internal bottlenecks in inter-processor communication that exist because of limitations in today’s point-to-point interconnect technologies.  Customers using systems based on Lightfleet technology will see significant benefits from increased efficiency in computing performance and data throughput, as well as reduced power consumption.  This Interconnect will first be utilized in a new type of server that will be manufactured on-site.  For more information, please visit our website at www.lightfleet.com or our AboutUs page at www.aboutus.org/lightfleet  Senior Optical Metrology / Test Engineer:  We are looking for an experienced and hands on Engineer who is well versed with variety of optical measurement techniques. The primary focus will be to identify off the shelf metrology tools and or design and develop custom tools for (1) test and characterization of optical components, electro-optical components, and optical systems (based on macro and micro optics) and for (2) providing active feedback in precision pick and place applications.  Duties will include:  Defining metrology requirements, identifying necessary hardware, and implementing the metrology process.  Designing and developing custom metrology tools as needed.  Interacting with mechanical design engineers to develop test and alignment fixtures for various sub-assemblies.  Working with different vendors. Providing specifications for custom or off the shelf scientific instrumentation.  Working with manufacturing to develop Optical metrology for Pass / Fail assessment of components, sub-systems, systems.  Minimum Requirements:  Bachelor’s Degree in Optical, Mechanical or Electrical Engineering. Degrees in Applied Physics or related fields will also be considered.  At least 8 years of work experience in the Optics field.  Solid foundation in geometric and physical optics.  Strong familiarity with Optical metrology techniques such as laser interferometry, laser triangulation, vision based metrology, ellipsometry, etc.  Knowledge of commercially available Optical Modeling and Design tools such as Zemax, ASAP, or LightTools.  Knowledge of using CCD cameras and commercially available image processing software.  Significant experience in working with optical metrology tools such as power meters, spectrometers, radiometers, beam profilers, integrating spheres, etc.  Familiarity with design and implementation of design of experiments.  Experience in performing gauge R&R.  Demonstrated analytical, experimental, and problem solving skills.  Experience working with technicians and contract manufacturers.  Experience working in a clean room and following ESD protocols.  Ability to communicate optical design requirements to Mechanical Engineers.  Ability to document results, write reports and test procedures, and present results to technical staff.  Highly innovative, self-motivated, and able to work both independently and in a group setting.  Desired Requirements:  Graduate Degree in Optical, Mechanical or Electrical Engineering. Degrees in Applied Physics or related fields will also be considered.  Experience in developing image processing algorithms.  Knowledge of Labview.  Ability to program in Visual C++ or Visual Basic.  Familiarity with high speed electro-optical testing (BER measurements, Jitter analysis, interpreting Eye Diagrams, etc.)  Experience with Opto-Mechanical design.  Experience with training operators and technicians.  For More Information:  Please visit our website at www.lightfleet.com or our AboutUs page at www.aboutus.org/lightfleet  To Apply:  Please send your resume to careers@lightfleet.com  Lightfleet Corporation is an equal opportunity employer.

National Research Council Postdoctoral Research Opportunities.  Biophysics Group, National Institute of Standards and Technology.  From K. A. Briggman, A. M. Chaka, E.J.Heilweil, A R. Hight Walker, J.Hwang, and D.F. Plusquellic  http://physics.nist.gov/bpg  We would like to call your attention to postdoctoral research opportunities with the Biophysics Group at the National Institute of Standards and Technology, located just outside Washington, D.C. The group emphasizes interdisciplinary research in selected areas of biophysics, photochemistry, spectroscopy, and optics.  We are looking for enthusiastic postdocs to design and implement projects in several areas, including the measurement of the near-field optical properties of nanometer-scale structures; femtosecond laser studies of dynamical processes in liquids, solids, and at interfaces; and linear and nonlinear optical probes of surface and interfacial structure. Present hot topics include:  • High-resolution THz studies of polypeptide structure and dynamics;  • Optical metrology of nanocrystals for quantitative biophysics;  • Enhanced Raman spectroscopy of biological molecules;  • Ultrafast condensed-phase dynamics of model biosystems;  • Computational methods to investigate dynamics and binding of small molecules to proteins;  • Vibrationally-resonant SFG studies of structure and dynamics of biomolecules (e.g., proteins) at biological interfaces.  Additional information about the group and about NIST is available on our web pages at http://physics.nist.gov/bpg  Positions will be filled through the NIST-National Research Council postdoctoral program, which is a competitive program open to U.S. citizens. The starting salary is $61,557 and there are government health, relocation, and other benefits. The research of a NIST-NRC postdoc in our group may be in any experimental or theoretical area listed on the accompanying sheets. These descriptions are based on a booklet, available from the NRC, which lists all postdoctoral research opportunities at NIST. Application forms and more information on the NIST-NRC program are available on request from the NRC, telephone number (202) 334-2760, and at http://www7.nationalacademies.org/rap/. The deadline for completing applications for this annual competition is February 1, 2009; the starting date for the two-year fellowships is July 2009 through January 2010.  Would you please show this material to students who might be interested in these postdoctoral positions? Prospective postdocs are encouraged to contact us immediately to discuss research and proposal topics. They may call Kimberly Briggman, Anne Chaka, Ted Heilweil, Angela Hight Walker, Jeeseong Hwang, or David Plusquellic at (301) 975-2358, -2481, -2370, -2155, -4580, or -3896, respectively. 

• Non-linear Optical Studies of Polymer, Biomimetic, and Biological Interfaces (RO# 50.84.41.B5559)  Many of the most interesting and important phenomena occur at interfaces, including heterogeneous catalysis, electron transport, molecular binding and transport at cell membranes, and nanoscale dynamics at polymer interfaces. We have developed a novel approach to the nonlinear optical technique of vibrationally resonant sum frequency spectroscopy (VR-SFS) to study molecular structure and dynamics at these interfaces. Forbidden in isotropic bulk media (e.g., liquids, gases, and solids), SFS is uniquely sensitive to interfaces. Our approach uses ultrafast (<50 femtosecond) lasers to generate infrared (IR) pulses that are spectrally very broad, enabling us to obtain the entire VR-SFS spectrum of a sample in a single laser pulse with ultrafast time resolution.  We are currently studying such problems as (1) the structure and assembly kinetics of biomimetic supported membranes from solution, (2) the orientation and kinetics of the membrane enzymes and polypeptides, (3) the structure and kinetics of polymer motion at polymer-polymer interfaces, (4) the structure and hybridization kinetics of DNA probes and targets immobilized on surfaces, and (5) the structure of peptide signaling sequences important for tissue engineering. In a new class of experiments, we are developing ultraviolet-IR doubly-resonant SFS to enhance our sensitivity in measuring the structure and dynamics of surface-immobilized membrane proteins and enzymes important for drug design, biomaterials, and biosensors. This interdisciplinary research uses many different techniques of interface preparation and characterization, and is done in collaboration with scientists in several NIST Divisions and from the National Institutes of Health. More information can be found at the Biophysics Group Web page at http://physics.nist.gov/bpg  Contact: Kimberly Briggman kbriggma@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/briggman.html  301-975-2358
   

• Multiphoton Techniques for Increased Molecular Sensitivity in Spectroscopy and Microscopy.  (RO# 50.84.41.B6757)  Multiphoton techniques are becoming the preferred methods for measuring and imaging the dynamic nature of biological components in living cells and tissues. We are exploring a variety of multiphoton  ibrational spectroscopies and microscopies for applications in the biosciences. We are combining state-of-the-art multiphoton optical spectroscopies with improvements in spatial resolution to obtain two- and three-dimensional images of biological samples. We are also accessing the native vibrational and electronic resonances in biomolecules to achieve increased molecular sensitivity. This negates the need for fluorescent dye or radioisotopic labeling in most biological samples. We invite applications to further the development of novel nonlinear spectroscopies and microscopies and/or to apply these techniques to solve dynamical problems in biology. For more information, please visit our Web site at Web page at http://www.physics.nist.gov/bpg  Contact:  Kimberly Briggman  kbriggma@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/briggman.html  301-975-2358
   

• Computational Methods to Investigate Dynamics and Binding of Small Molecules to Proteins.  (RO# 50.84.41.B6252).  Current research focuses on the need to better understand and quantify the free energy of binding of small molecules to protein targets to enable robust virtual screening of pharmaceutical candidates and chemical probes to query protein function. The majority of drugs are small molecules that function by reversible non-covalent binding to proteins, thereby modulating their biological activity. Virtual high throughput screening is routinely utilized in the pharmaceutical industry to select molecules from large libraries as potential drug candidates. This selection is performed by “docking” compounds to the drug binding site and calculating the “score” by which they are ranked. The best-scoring molecules bind most tightly and are selected as lead candidates. However, recent research has revealed that ranking results of current docking-and-scoring methods do not agree with experimental binding affinities. It is not known how much of the discrepancy between calculated docking scores and experimental binding affinities is due to computational limitations or experimental variability.  Therefore, our aim is to develop and evaluate a series of Standard Reference Simulations (SRS) to calculate such ligand-receptor binding energies, quantify the uncertainty introduced by assumptions and simplifications, and assess the accuracy of the range of methods currently available from classical force fields to ab initio dynamics. We are working to delineate the fundamental chemistry and physics that drives the process of binding, including the balance of enthalpy and entropy, van der Waals and electrostatic forces, hydrogen bonding, protein dynamics, and solvation/de-solvation effects. This project is closely integrated with experimental and computational efforts at NIST, as well as the Center for Advanced Research in Biotechnology (a joint center between NIST and the University of Maryland Biotechnology Institute), and pharmaceutical companies to validate the theoretical developments. Contact:  Anne Chaka  anne.chaka@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/chaka.html  301-975-2481.
   

• Ultrafast Infrared and Terahertz Spectroscopy of Condensed-Phase Dynamics.  (RO# 50.84.41.B1780).  Pulsed laser methods are used to measure ultrafast photochemistry and energy dynamics in the condensed phase. These include tunable mid-infrared (IR) or visible/ultraviolet (UV) excitation with multichannel mid-IR or Terahertz (THz) detectors for time-resolved spectroscopy, hyperspectral imaging, and related nonlinear spectroscopies. Systems investigated include carriers in semiconductors and organic thin films, metal plasmons, photoreactions, biopolymers, and molecular vibrational energy transfer of inorganic or organic species in solution in crystals and on surfaces. Emphasis is placed on developing vibrational probes to investigate organic and protein/peptide systems, solar cell and electronic-vibrational energy transfer processes, photochemistry of organometallic “switch” compounds, and dynamics of model biosystems of hydrogen-bonded solution-phase complexes. We also examine polymerization and heterogeneous catalytic reactions, coherent control by chirped femtosecond IR vibrational overtone excitation of metal-carbonyls, and dissociation and recombination rates of nucleic acid base pairs, amino acids, sugars, and related biosystems.  Apparatus includes (1) two Ti:Sapphire 20 fs oscillators, each with kHz regenerative amplifiers and UVvisible-IR OPAs; (2) a THz pump-probe spectrometer and imaging setup; (3) CW-modelocked, Nd+3 Vanadate system with three synch-pumped 400 fs, 20 Hz amplified dye lasers; (4) nonlinear crystals for sum, mid-IR, and THz generation; (5) CCD and mid-IR focal-plane arrays for multichannel detection and imaging applications; and (6) a THz Fourier transform infrared spectrometer for acquiring static spectra. For more information, please see our Web pages at http://physics.nist.gov/bpg  Contact: Ted Heilweil  edwin.heilweil@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/heilweil.html  301-975-2370.
   

• Enhanced Raman Spectroscopy of Biological Molecules.  (RO# 50.84.41.B6812)  Research efforts are underway to probe biological molecules with Raman spectroscopy in three states—crystal, semi-solid, and solution—to illuminate the structural transformations that occur across phases. The optical characterization of biological molecules using vibrational spectroscopy supplies critical, detailed structural information unavailable through fluorescent measurements and unhampered by water absorption. To observe Raman-active vibrational modes, physiological concentrations, enhancement of the Raman scattering cross-section is often necessary. Enhancement factors of orders of magnitude are achievable through resonance Raman (i.e., matched laser excitation with electronic transition, or surface enhanced Raman), where anisotropic, metallic nanoparticles of silver or gold are placed in close proximity to the molecule, either in solution or on a surface. Two Raman spectrometers are available for this effort, including a microscope and multiple laser lines. Also exciting is a combination of Raman microscopy and microfluidic technology to monitor the vibrational spectra of biomolecules while rapidly changing the buffer environment to induce conformational changes. Raman spectroscopy can be used to query the structure of membrane proteins immobilized in supported, synthetic lipid bilayers both on a surface and in suspended liposomes. Furthermore, Raman microscopy can be used to view protein concentration gradients throughout a cell.  Another angle of our research effort focuses on the low-frequency torsional modes (<200 cm-1) of proteins and polynucleotides. This region of the spectrum is rich with dynamical and structural information. A triple-grating monochromator provides the rejection capabilities necessary for observing these low-frequency vibrations. A companion molecular modeling effort is absolutely critical due to the complexity and nascency of this spectroscopic region, and is implemented with the aid of a 6-node UNIX cluster and computational software. The combination of this effort, with both its experimental and theoretical sections, with the complementary CW Terahertz Spectroscopy effort described elsewhere, greatly increases our ability to assign torsional vibrational modes to the flexibility of the biological molecule and provide the force field information needed to delineate the driving forces responsible for protein structure, folding, and function.  Contact:  Angela Hight Walker  angela.hightwalker@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/hight.html  301-975-2155.
   

• Nanoparticle Engineering, Production, Assembly, and Characterization.  (RO# 50.84.41.B6811)  Magnetic nanoparticles have shown great potential for applications not only in catalysis and magnetic recording, but also in medical sensors and biomedicine. Their biological applications include contrastenhancing agents for magnetic resonance imaging (MRI) and site-specific heat sources to destroy tumor tissue. Metallic nanoparticles such as gold, silver, and copper also show promise for a variety of applications from energy storage to biotechnology. We are particularly interested in anisotropic nanoparticles (e.g., rods, stars) with novel optical properties. Our research program focuses on engineering nanoparticles with desired physical, chemical, and stability properties through thermodecomposition.  These properties are being studied specifically for their relevance to Nano-EHS and toxicology. Synthesis, assembly, characterization, and application of nano-engineered materials are all critical components of the program. A wide variety of tools are available for this effort, including HRTEM, SEM, UV-VIS, SQUID, and SERS.  Contact:  Angela Hight Walker  angela.hightwalker@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/hight.html  301-975-2155.
   

• Optical Spectroscopies of Carbon Nanostructures.  (RO# 50.84.41.B6810)   The multibody effects in the optical spectra of single-walled carbon nanotubes (SWCNT) and other carbon nanostructures are investigated using resonant Raman spectroscopy. Resonance enhancement  of the Raman scattering intensity of the radial breathing mode in SWCNTs is used as a probe of tube chirality and of one-dimensional electronic structure. The confocal magneto-Raman microscope at NIST permits continuously tunable laser excitation from the near-infrared to the ultraviolet. This novel Raman facility consists of a microscope capable of working over a wide range of temperatures (T = 4.2-300 K) and magnetic fields (H = 0-8 T) coupled to a triple grating spectrometer with ultimate Raleigh rejection capabilities, thereby permitting low-frequency or Terahertz Raman spectroscopy. As a member of a multidisciplinary NIST team focused on nanometrology for carbon nanostructures, we obtain measures of sample characteristics of value to academic, industrial and nano-environmental, - health, and -safety (Nano EHS) communities such as sample quality, purity, alignment, and physical features (e.g. diameter and length). Unprecedented nanotube samples are available permitting the study of fundamental physical properties. Characterization of bulk, single, DNA-wrapped, suspended, and nanoparticle-functionalized SWCNT samples are all of interest to the program. Furthermore, the unique optical properties of complementary materials such as grapheme are critical components.  Contact: Angela Hight Walker  angela.hightwalker@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/hight.html  301-975-2155.
   

• Dynamical Molecular Imaging of Nanoscale Structures and Biological Functions of Cell Membranes.  (RO# 50.84.41.B7011).  Cellular membranes are important not only to maintain cell structure but also to control cellular functions such as signal transductions and immunological reactions. Elucidation of the unique properties of cell membranes, working together with other cellular components, is essential to understand the response of vertebrate cells to infectious agents and pathogens such as parasites and bacterial cells. In particular, an understanding of changes in the dynamic structure of cell membranes during the intracellular cycle of pathogens is critical to the design and implementation of preventive measures against the cellular infection. Therefore, we continue to develop and apply advanced live cell imaging techniques to enhance temporal and spatial resolutions and enable the dynamical study of the cellular mechanism in vertebrate cells, leading to a better understanding of membrane protein dynamics at the single cell level. To enhance the measurement resolutions, we develop and apply realtime total internal reflection fluorescence (TIRF) microscopy combined with other dynamical imaging techniques, including time-resolved Förster resonance energy transfer (FRET) and real-time video (RTV) microscopy. We also developed an immunofluorescence assay using bio-conjugated nanocrystals (quantum dots, metal particles, and nanoshells) to identify and quantify specific cellular structures and dynamics at the nanoscale level. We are currently extending this approach to the single particle tracking (SPT) study of membrane-bound proteins labeled with other novel molecular probes to elucidate the influence of pathogens to cells. Available equipments and expertise includes (1) laser confocal microscopes enhanced with a cooled charged-coupled device (CCD) and intensified CCD cameras capable of RTV imaging; (2) a variety of cw and pulsed lasers coupled to a fast polarization modulation system; (3) qualitative and quantitative low-light-level RTV microscopy systems for in vitro studies of infecting pathogens; (4) a TIRF system capable of single molecule sensitivity with a high signal-to-noise ratio; and (5) a capability of wet bench chemistry for immunocytochemistry, biochemistry, gene expression, and molecular biology studies in collaboration with research laboratories at NIH. This is a highly interdisciplinary research opportunity in collaboration with other institutes and agencies. For more information, visit our Web site at http://physics.nist.gov/Divisions/Div844/facilities/omb/omb.html  Contact:  Jeeseong Hwang  mailto:jeeseong.hwang@nist.gov http://physics.nist.gov/Divisions/Div844/staff/Gp8/hwang.html  301-975-4580.
   

• High-Throughput Opto-Immunoassay Platforms for Quantitative Biomedical Diagnosis.  (RO# 50.84.41.B6375)  Cancer progression may occur by predictable alterations at the mRNA and protein level, including activation of pathways that favor cell growth and/or inactivation of pathways that lead to apoptosis or cellular differentiation. Characterizing these molecular alterations will help us to identify clinically aggressive tumors. For instance, global gene expression analysis may provide insight into the nature of prostate cancer and potentially permit identification of tumors that are likely to behave aggressively.  However, testing this hypothesis in humans presents a significant challenge, requiring integration of multiple scientific disciplines and development of novel experimental strategies. Among other approaches, our project focuses on developing and applying novel combinatorial molecular pathology methods involving a multilayered molecular capturing system and advanced optical techniques to enhance the speed and accuracy in identifying biomarkers involving cancers, tumors, and pathogens in cells and tissues at the molecular level. These methods include novel combinatorial optoimmunoassays capable of high-throughput analyses of biomarkers such as cancer genes and proteins; engineered nanocrystals (quantum dot and metal nanoshell) biosensors capable of targeting, analyzing, and photo-thermally eradicating tumor cells and pathogens; and advanced laser-based optical imaging capabilities to understand the fundamental cellular mechanism involving specific biomarkers. Available equipment and facilities include (1) a full-field microscope equipped with a cooled charge-coupled device camera and spectrometer capable of single molecule studies, (2) a single- or multi-photon confocal microscope associated with a variety of lasers such as Ar/Kr cw and TiSap pulsed lasers, (3) integrated cellular imaging platforms capable of time-resolved study of cells in a variety of contrast mechanisms and geometries, (4) micro biochip arrayer, (5) access to NIST’s microfluidics fabrication facility, and (6) a layered expression scanning system for multiplex molecular analysis. We have access to clinical specimens through collaborations with laboratories at NIH. This is a highly interdisciplinary research opportunity in collaboration with other institutes and agencies. For more information, visit our Web site at http://physics.nist.gov/Divisions/Div844/facilities/omb/omb.html  Contact:  Jeeseong Hwang  mailto:jeeseong.hwang@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/hwang.html  301-975-4580.
   

• Near-Field Interactions of Novel Nanoprobes in Bio-Inspired Self-Assembled Hybrid.  Nanomaterials.  (RO# 50.84.41.B7010).  We have been developing and employing nanoscale optical and chemical imaging techniques to study nanoscale structures and dynamics in hybrid organic materials, biomimetic membranes, and biological cells. We have installed a variety of biological probe microscopies (e.g., near-field scanning optical microscopy [NSOM] and chemical force microscopy [CFM]) employing functionalized atomic force microscopy (AFM) tips. Current research involving these techniques focus on enhancing the sensitivity and the temporal, spatial, and spectral resolution, as well as broadening the application of these techniques towards nanoscale characterization of real-world samples. Such applications include the study of bio-inspired, self-assembled biological materials; organic electronic materials; and optoelectronic materials and devices involving material excitations (e.g., excitons, plasmons) at the nanoscale. Our new approach employs near-field optical interactions between a nanoscale light source (e.g., field-enhanced metal probe, luminescent nanocrystal, and fluorescent molecule) and a material excitation (e.g., surface plasmon and exciton) in nanoscale materials (e.g., nanocrystals, nanoshells, and nanotubes). Our interests center on studying the fundamental mechanisms of these near-field interactions, as well as on developing and applying spectrally-resolved nanoscale imaging capabilities by employing spatially and temporally enhanced molecular elements in bio-inspired self-assembled hybrid materials. Available equipment consists of a facility to manufacture metallic and fiber NSOM probes (optical fiber puller, FIB, SEM), scanning probe microscopes (NSOMs and AFMs), a combined confocal-AFM/NSOM system, visible and Raman spectrometers, a total internal reflection fluorescence microscope, a NIR-DIC microscope, a variety of cw and pulsed laser systems, and more. A variety of self-assembly techniques are also being developed to engineer nanocomplexes of biomolecules and nanomaterials for a variety of potential applications in biological and biomedical studies including cellular diagnostics, repair and modification, cancer detection, in vivo imaging, biological warfare agent detection, and drug research and development. This is a highly interdisciplinary research opportunity in collaboration with other institutes and agencies. For more information, visit our Web site at http://physics.nist.gov/Divisions/Div844/facilities/omb/omb.html  Contact:  Jeeseong Hwang mailto:jeeseong.hwang@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/hwang.html  301-975-4580.
   

• Optical Metrology of Nanocrystals for Quantitative Biophysics.  (RO# 50.84.41.B6758).  Colloidal nanocrystals (NCs) are known to exhibit many desirable optical characteristics enabling high sensitivity, high specificity, and high throughput multiplexed detection of multiple targets in a complex environment. Such optical properties include high fluorescence efficiency, photostability, and unique optical spectra, enabling the use of NCs in the development of next generation nano-engineered elements and devices such as nano-optoelectronic elements, chemical and biological nanosensors, and nanoscale biomedical imaging probes. Despite the excellent photochemical and physical properties of NCs, the optical properties of NCs have been observed to be strongly dependent on their nanoenvironment.  Therefore, a complete understanding of the physical and optical characteristics of NCs for a variety of biomimetic parameters is essential, especially for the quantitative application in biophysical and biomedical research. The following technical needs are identified: (1) a platform to fabricate and characterize NC samples prepared under environmental conditions and environmental variables for the rapid characterization; (2) an integrated measurement system of nano-characterization tools to  quantitatively correlate optical properties and chemical or physical conditions of NCs in a controlled environment; and (3) measurement strategies and standards to assess NC properties when they are delivered into complex biological environments such as cells, tissues, and organisms.  This project focuses on exploring the use of NCs as sensors and probes in quantitative biomedical and biophysical applications. Our approach is to produce microarrays of high-throughput combinatorial NC samples involving a variety of biomimetic parameters, to enable simultaneous optical and physicochemical characterization of single NCs using advanced laser optics and scanning probe microscopy techniques, and to manufacture nanoscale self-assembly systems and evaluate their properties in complex biomimetic environments. A variety of self-assembly techniques are being developed to engineer nanocomplexes of biomolecules and nanomaterials for a variety of potential applications in biological and biomedical studies including cellular diagnostics, repair and modification, cancer detection, in vivo imaging, biological warfare agent detection, and drug research and development. More information can be found at our Web site, http://physics.nist.gov/Divisions/Div844/facilities/omb/omb.html  Contact: Jeeseong Hwang  mailto:jeeseong.hwang@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/hwang.html  301-975-4580.
   

• High-Resolution THz and Ultraviolet Studies of Polypeptide Structure and Dynamics.  (RO# 50.84.41.B5923).  Current research focuses on two major areas. CW THz laser spectroscopy (from 2 cm-1 to 150 cm-1) is used to probe the lowest frequency vibrational modes of polypeptides critical to their folding motions and function. Samples are prepared on waveguide interfaces, in solid polyethylene matrices, liquid water, and ice and probed using a high-resolution cw THz spectrometer. The waveguide technique enhances detection sensitivity by 10-fold (thin film thicknesses of < 2 μm) and reduces spectral congestion from inhomogeneous broadening by 5-fold. Since the waveguide supports only one polarization, the spectral intensities are sensitive to the crystal growth patterns at the interface. When this orientation is measured using x-ray crystallography, detailed information about the types of nuclear motions is obtained. THz spectra are found to be extremely sensitive to temperature and the local environment. For example, the THz spectra of the hemi-hydrated and dehydrated forms crystalline trialanine (anti-parallel beta-sheet) are vastly different although their Fourier-transform mid-infrared spectra are nearly identical. In contrast, THz spectra of hydrophobic dipeptide nanotubes with and without water in the pore regions are nearly identical except for a small red-shift. Furthermore, changes in the available thermal energy at 4.2 K and 300 K leads to substantial changes in the vibrational partition functions (1 to >108 for biotin), thereby providing access to the anharmonic regions of the potential energy surfaces. Vibrational models that include mechanical anharmonicity adequately explain the observed lineshapes. Much of this research is aimed at a fundamental understanding of the underlying biophysics of these systems. The systems investigated are small enough to permit application of quantum chemical theories to predict the types of motions associated with the THz spectral features. THz spectroscopy of polypeptides offers great promise for studies of protein folding and water transport dynamics. Current efforts focus on (alanine)n, n=3,10, in α-helix and β-sheet conformations deposited on waveguide interfaces.  In a second area, high-resolution ultraviolet laser and cavity ringdown techniques are used to determine the three-dimensional molecular structures of methyl terminated peptide mimetics in the gas phase and of chirally pure transmembrane model peptides supported in lipid bilayers at glass/water interfaces.  Linear dichroism studies assembled in lipid bilayer membranes measure the orientation of the indole chromophore relative to the membrane interface. Circular dichroism signals are sensitive to the local molecular conformation of the attached peptide backbone. These studies provide insight into the influence of the solvent and interfacial structure on the chiral selectivity that controls bioactivity.  Contact:  David Plusquellic  mailto:david.plusquellic@nist.gov  http://physics.nist.gov/Divisions/Div844/staff/Gp8/plusquellic.html  301-975-3896.