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Watt's Up College of Optical Sciences News for October 11, 2007
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Today -- Optical Sciences Colloquium -- 3:30 p.m. -- Meinel 307
Kristian Helmerson of the National Institute of Standards and Technology will present Vortices and Persistent Currents: Rotating a Bose-Einstein Condensate using Photons with Orbital Angular Momentum. Brian Anderson and Poul Jessen are the hosts. Abstract: The interaction of photons with atoms inevitably involves the exchange of momentum. The transfer of spin angular momentum from light to an atom has been known for almost a century and can be used, very effectively, to change the internal state of an atom. Similarly, the past couple of decades have witnessed a tremendous growth in the use of light to control the center-of-mass motion of atoms. For example, the linear momentum of light can be utilized to laser cool and trap atoms. Light, in addition to carrying spin and linear momentum, can also carry orbital angular momentum. The orbital angular momentum of light, which is associated with its spatial mode, has been used to rotate macroscopic objects; however, the rotation of atoms due to the orbital angular momentum of photons has not been directly observed.
I will describe experiments in which we demonstrate [1] the coherent transfer of the orbital angular momentum of a photon to an atom in quantized units of h. Using a 2-photon stimulated Raman process with Laguerre-Gaussian beams, which carry orbital angular momentum, we generate an atomic vortex state in a Bose-Einstein condensate (BEC) of sodium atoms. We show that the process is coherent by creating superpositions of different vortex states, where the relative phase between the states is determined by the relative phases of the optical fields. Furthermore, we create vortices of charge 2 by transferring to each atom the orbital angular momentum of two photons, each with orbital angular momentum h.
We subsequently use this technique to generate rotational flow of a BEC confined in a toroidal shaped trap. The toridal trap is formed by using a blue detuned laser beam to exclude atoms from the central region of an elliptically shaped magnetic trap. We measure that the flow of atoms persists for up to 10 seconds, which we interpret as the first direct evidence of a persistent current in a superfluid Bose gas. Stable flow was only possible in the multiply-connected geometry of the toriodal trap, and was observed for a BEC fraction as small as 15%. We also observed flow with higher angular momentum (winding number), and its splitting into singly-charged vortices when the trap topology was changed from multiply- to simply-connected.
References:
[1] M. F. Andersen et al., Phys. Rev. Lett. 97, 170406 (2006).
Something to Think About
From Will Rivera. Dear Colleagues: Once again the October Support Campaign is underway and soon you will receive appeal information in the mail. Please take a moment to review the contents and consider the impact you can make on this program and the future of Optical Sciences. Any support is appreciated and gifts over $250 qualify for placement on the OSC donor wall. If you have any questions about the campaign please contact me directly and I’m happy to assist. I can be reached by telephone at 520-626-8754 or by e-mail at wrivera@optics.arizona.edu Or, if you prefer, please visit our Web site at www.optics.arizona.edu/givingback
Also this month the University conducts the UA Cares, “Campaign for Community Giving,” where you have the opportunity of supporting the United Way or any non-profit organization of your choosing. If you have questions regarding that program please contact Jamie Bommer this year’s coordinator. Soon information will arrive in your college mailbox with instructions on how to give. Jamie can be reached by telephone at 520-621-8154 or by e-mail at jgrace@optics.arizona.edu
Your generous donations, regardless which campaign you select, are fully tax deductible in accordance with IRS regulation. Thank you for your attention and continued support.
Sports Friday
From James Johnson. Hello Students, Staff, and Faculty, Tomorrow, October 12, Sports Friday we'll' play water polo over at the Rec Center Pool. It'll be one of the last few good Fridays to be in the water and you don't want to miss it. We'll be meeting around 5:30 at the West End of the pool.
Be sure to bring your suit and goggles! A towel and a lock can be rented for a dollar.
See you there.
UA's 2007 Holiday Closure is Approaching
From Stella Hostetler. The University will be closed from December 24 through January 1. This gives us a great Winter break: our last day of work for 2007 is Friday, December 21 and we return to work on Wednesday, January 2, 2008.
The OSC Payroll Office will need to know how to record your hours during this time period. Please submit the appropriate Holiday Closure memo to Payroll, Meinel 421, no later than Monday, December 3.
The forms can be found online at http://www.optics.arizona.edu/hr/forms.htm
Happy Birthday and Best Wishes for a Wonderful Year
Jet Propulsion Laboratory Campus Visit
From Tiffany Snow. JPL Recruiter. Representatives from JPL, the Jet Propulsion Laboratory, will host an Information Session with UA's career services office on Monday, October 15 in the Student Union's Tucson Room from 5:30 to 7:30 p.m. We will also conduct employment interviews (Optical Engineering and Electrical Engineering) with the career service office on Tuesday, October 16. Also on October 16, we will have a Information Session in the Optical Engineering Building from 6:00 to 7:30 p.m. On Wednesday, October 17, we will conduct interviews in the Optical Engineering Building Career Services Building. The deadline for students to sign up for interviews is Sunday, October 7. We have made quite a few hires from your University and look forward to coming back again! JPL, located in Pasadena, California, is affiliated with Caltech and NASA and our charter is primarily the exploration of the solar system with robotic spacecraft. Contact: Tiffany M. Snow, Recruiter, University Relations, Jet Propulsion Laboratory, California Institute of Technology. Telephone: 818-354-8160. E-mail: Tiffany.M.Snow@jpl.nasa.gov URL: http://www.jpl.nasa.gov Employment: http://careerlaunch.jpl.nasa.gov
On Campus
October 12, 2007 -- Physics Colloquium -- 2:30 and 3:00 p.m. -- PAS 224
October 15, 2007 -- BME Seminar -- 2:00 p.m. -- Keating 103
October 16, 2007 -- BME Faculty Candidate Seminar -- 11:00 a.m. -- MRB 201
Optical Sciences Calendar
Please check out our calendar at
October 11, 2007 -- OSC Colloquium -- 3:30 p.m. -- Meinel 307
October 12, 2007 -- OSC Sports Friday -- 5:30 p.m. -- Location is TBD
October 16, 2007 -- JPL Company Interviews -- Contact Jamie Bommer
October 16, 2007 -- JPL Information Session -- 6:00 p.m. -- Contact Jamie Bommer
October 17, 2007 -- OSC Soccer Practice -- 5:15 p.m. -- UA Mall
October 17, 18, 19, 2007 -- Oceanit Company Interviews -- Contact Jamie Bommer
October 18, 2007 -- OSC Colloquium -- 3:30 p.m. -- Meinel 307
October 23, 2007 -- Veeco Metrology Seminar and Workshop -- All Day -- Meinel 410
Optics Employment
Please check out additional
opportunities at
Assistant Professor of Physics. Eastern Illinois University. The Physics Department at Eastern Illinois University seeks qualified candidates with a Ph.D. in Physics or a closely related field for a full-time tenure-track assistant professor position beginning Fall 2008. The successful candidate must demonstrate a strong commitment to and enthusiasm for undergraduate physics education through classroom teaching and mentorship of undergraduate student research. The successful applicant must be able to develop and maintain an active undergraduate research program. All candidates that have the potential to supplement an existing strength within the department will be considered. An experimental physicist is preferred with particular interest in candidates having significant experience in optics and lasers or radiation/health physics. Major departmental equipment includes a 4 watt CW Ar-ion laser, a 50 J/pulse excimer laser, several nitrogen pumped dye lasers, a 1m monochromator, an X-ray fluorescence system, a thin film deposition system, and an observatory with a 16" computer-controlled telescope. Applicants should submit a letter of application, a statement of teaching experience and philosophy, a vita, and a statement of research interests with plans (all of which may be submitted electronically), and should arrange to have official undergraduate and graduate transcripts and three letters of recommendation sent to: Dr. Leonard Storm, Chair. Physics Department, Eastern Illinois University. 600 Lincoln Avenue, Charleston, IL 61920. E-mail: lestorm@eiu.edu Review of candidates will begin November 1st and continue until the position is filled. Eastern Illinois University is an equal opportunity, equal access, affirmative action employer committed to achieving a diverse community.
Postdoc. Rice University. Postdoctoral Position in Optics and Bio-engineering is available in the laboratory of Prof. Tomasz Tkaczyk in the Department of Bioengineering at Rice University. In our research we develop modern optical instruments for biological and biomedical applications. We combine new technologies in optics, opto-mechanics, electronics, software and bio-chemical materials to solve problems of medical diagnosis and detection for both clinical and remote environments. We are also interested in advancing imaging techniques to enhance performance and information content in acquired images. We look for a postdoctoral fellow interested in optical design, fabrication, assembly and imaging with miniature optical systems. The researcher will work on design and building instruments combining high resolution imaging with bio-chemical contrast agents like gold nanoparticles or quantum dots to deliver information about the early stage of the disease (cancer, infectious diseases). To assure wide applicability of instruments they have to be inexpensive and easy to use. Examples of targeted systems include high resolution endoscopes, multiple FOV endoscopes and optical platforms for point-of-care (POC) applications. In-expensive optical platform can be applied for example for imaging and spectroscopy to enable efficient and easy screening. As mentioned above a significant part of our research is based on high precision fabrication and assembly for integrated miniature instruments. Therefore, we are constantly searching for new fabrication/assembly techniques and new optical and opto-mechanical materials. Engaging in new technologies will be an important part of activities of a postdoctoral researcher. Modern technologies give us new capabilities not possible in more classical approaches. For example grayscale lithography with solgel allows us to easily build a new class of optical instruments (arbitrary surfaces) not restricted to rotational symmetry. At the same time it is a perfect technology for mass production using processing similar to that applied in electronics. Constant material advancements to enable building high power or color corrected miniature systems is always needed. Responsibilities: Responsibilities of the postdoctoral fellow will include: Very active engagement in the research on development of optical instrumentation pursued by group. Publishing research papers. Assistance with writing grant proposals. Assistance in advising graduate students. Minimum Requirements. Ph.D. degree related to optical engineering, imaging or applied optics. Optical design knowledge using commercial software packages (for example ZEMAX, Code V etc.) Experimental lab experience. About Rice and Houston Rice is constantly ranked as one of nation’s best teaching and research universities. It is a member of world’s largest medical center (Texas Medical Center). The Department of Bioengineering at Rice University is consistently among 10 best bioengineering graduate programs in US. Rice is situated next to the Texas Medical Center and in the Museum district of Houston. Houston is the fourth largest city in US giving all benefits of a large metropolis. On the other hand living in Houston is affordable and delivers a lot of accessible choices for accommodation, entertainment or business. Procedures: Rice University is committed to affirmative action and equal opportunity employer and offers competitive postdoctoral salary and benefits. The position is opened from October 5th 2007 until filled. To apply please send your resume and letter on research interests directly to Professor Tkaczyk at ttkaczyk@rice.edu For more information visit http://www.owlnet.rice.edu/~tt3/
Agency Listing. Development Engineer. Industry: Laser. Direct Placement. Location: Washington State (Seattle Area). Salary: DOE. Start: Immediate. BS – Optical Engineering, physics or related field, with strong focus on practical and theoretical optics. Minimum 3 years technical experience testing optical systems and lasers, preferably in a high tech R&D, product development or manufacturing environment. High degree of technical integrity and commitment to project completion. Duties/Responsibilities: Primary responsibilities of this position are to test parts, components and systems for laser products, including: Perform a variety of complex experimental tests on equipment and evaluate the results. Perform lab functions, such as optical alignment, beam quality measurements, air and water cooling of diode lasers, optical setups, fiber/diode laser mounting, pumped solid state lasers. Resolve engineering problems of moderate complexity. Contact: Matt Sawicki. Lead Recruiter. The Talley Group. (425)753-506. sawickim@thetalleygroup.com |
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Dear Alumni: