Photonics

Albert Einstein Hologram - University of Arizona Optical Sciences - PhotonicsResearch in photonics at the College of Optical Sciences ranges in scope from fundamentally new tools, such as small-footprint, high-throughput multiphoton microscopes, through exceptionally high-power semiconductor lasers, to components and systems for next-generation optical networks for both the Internet and data centers, and into consumer equipment like 3-D displays. New areas are constantly explored by our nine faculty in the specialty, as photonics becomes more pervasive in our lives. Communications, displays, medicine, manufacturing and imaging are just a few applications.

The re-writable hologram of Albert Einstein shown as a 2-D figure was created with state-of-the-art technology developed by our group. Professor Masud Mansuripur, the college's Chair of Optical Data Storage, recently has provoked considerable controversy by reminding the physics community that the commonly used Lorentz force law for charged particle motion is not relativistically invariant when applied to magnetic materials in the presence of an electric field; the suggested remedy is to return to an alternative force law proposed by Albert Einstein in 1908.

To review past updates, see the Photonics Research Updates Archive page.

What's New in Photonics

Assembly of multicomponent structures from hundreds of micron-scale building blocks using optical tweezers

Date Published: August 17, 2021

College of Optical Sciences Research

Large-scale microassembly using optical tweezers. a Scanning electron microscope (SEM) image of a 3D periodic 8 × 8 × 7 simple cubic lattice consisting of alternating biotin-coated and streptavidin-coated 1 μm polystyrene spheres. Inset: 3D layout of the two components. b SEM image from (a) with overlaying spheres in red along the front, side, and top faces of the structure, which are used to estimate a mean absolute 3D positional error of 180 nm. c High-magnification SEM image of a corner of a 6 × 6 grid of alternating biotin- and streptavidin-coated 1 μm spheres. The streptavidin-coated spheres exhibit a rougher surface. d–f Optical microscope images of the full structure in (c). The biotin-coated spheres are green-fluorescent, while the streptavidin-coated spheres are red-fluorescent. The brightfield image is shown in (d), and the fluorescence image obtained using a FITC filter set is shown in (f). A mixed modality image (brightfield + fluorescence) is shown in (e).

The fabrication of three-dimensional (3D) microscale structures is critical for many applications, including strong and lightweight material development, medical device fabrication, microrobotics, and photonic applications. While 3D microfabrication has seen progress over the past decades, complex multicomponent integration with small or hierarchical feature sizes is still a challenge. Dr. Jeffrey Melzer and Dr. Euan McLeod have precisely fabricated 3D microstructures from two types of micron-scale building blocks linked by biochemical interactions using an optical positioning and linking (OPAL) platform based on optical tweezers technology. It is anticipated that OPAL will enable the assembly, augmentation, and repair of microstructures composed of specialty micro/nanomaterial building blocks to be used in new photonic, microfluidic, and biomedical devices. Read the published article.

High-Speed Lens-Free Holographic Sensing of Protein Molecules Using Quantitative Agglutination Assays

Date Published: August 17, 2021

College of Optical Sciences Research

A look at the setup of the new QLAB sensor demonstrating its ability to detect Brownian motion in a liquid sample without blur.

Accurate, cost-effective, easy-to-use, and point-of-care sensors for protein biomarker levels are important for disease diagnostics. A cost-effective and compact readout approach that has been used for several diagnostic applications is lens-free holographic microscopy, which provides an ultralarge field of view and submicron resolution when it is coupled with pixel super-resolution techniques. Dr. Euan McLeod with Dr. Zhen Xiong and Mr. Colin Potter have developed a quantitative large-area binding (QLAB) sensor. The high-speed light source provides, for the first time, pixel super-resolved imaging of >104 2 μm beads in solution undergoing Brownian motion, without significant motion blur. These beads are coated with capture agents, resulting in bead clustering when in the presence of a specific target protein. The QLAB sensor holds promise for point-of-care applications in low-resource communities and where protocol simplicity is important. Read the published article.

How a Tiny Loop of Light Could Help Fight COVID-19 (and So Much More)

Date Published: June 22, 2021

College of Optical Sciences Research

Judith Su, an assistant professor of biomedical engineering and optical sciences, runs the UArizona Little Sensor Lab, where researchers are finding ways to use a one-of-a-kind technology to address some of the medical community's most pressing problems. (Photo: Chris Richards / University of Arizona)

FLOWER: How a Tiny Loop of Light Could Help Fight COVID-19

At the Wyant College of Optical Sciences’s Little Sensor Lab, researchers are building sensors that have three key advantages: They can detect low concentrations of substances, provide results in 30 seconds or less, and they don’t need to label or amplify the substance they’re trying to detect. But perhaps the best part? They may be helpful in detecting and treating COVID-19, cancer and scores of other harmful or deadly contaminants.

This technology could be useful in medical diagnostics, environmental health monitoring and detecting chemical threats, said Judith Su, Ph.D., assistant professor of optical sciences and biomedical engineering. In fact, it shows such promise that it was awarded a $1.82 million grant from the National Institutes of Health.

Read the full article

Accuracy of the Skin Depth Correction for Metallic Nanoparticle Polarizability

Date Published: June 20, 2019

College of Optical Sciences Research

Simulation geometry. (a) Far field scattering calculations are performed for solid and hollow gold nanospheres illuminated by plane waves. (b) Optical force calculations are performed on gold nanospheres displaced laterally by Δx from the optical axis of a Gaussian beam with λ/2 beam waist.

The McLeod lab's research shows that light scattering and optical trapping calculations based on the full volume of nanoparticles is more accurate than calculations based on only the skin depth. This study suggests that a simpler model is more accurate than the skin depth model, which had been widely used by researchers for the past three decades. Read the published article.

Little Sensor Lab

Date Published: September 26, 2017

Microtoroid optical resonator

Microtoroid optical resonator

Judith Su's lab centers on label‐free single molecule detection using microtoroid optical resonators. The technique called FLOWER (Frequency Locked Optical Whispering Evanescent Resonator) uses frequency locking in combination with balanced detection and data processing techniques to achieve single molecule sensitivity and fast detection times.

The lab's main focus is on basic research, and translational medicine through the development of miniature field portable devices as a tool to detect, understand, control, and treat various diseases. The lab is also developing chemical sensors for environmental monitoring, reducing threats, assisting national defense, and enabling clean sport competition.

 

Masud Mansuripur Interviewed by SPIE Newsroom

Date Published: September 21, 2017

Masud Mansuripur - SPIE Interview

A screen capture of the SPIE Newsroom of Professor Masud Mansuripur.

Professor Masud Mansuripur was interviewed by SPIE in February, 2017. Entitled Developing a Theory of Optical Momentum, the interview can be viewed on the SPIE Newsroom website.

ARPA-E MOSAIC Program

Date Published: July 26, 2016

Robert A. Norwood's ARPA-E Mosaic schematic

Schematic showing basic approach to a high efficiency solar panel.

Professor Robert A. Norwood's research portfolio consists of work ranging from nanoscale electro-optic modulators to 40 square meter hybrid solar energy systems. A common theme that cuts across this 10 order of magnitude change in length scale is the coupling of fundamental optical materials and device physics to emerging applications with significant impact. The Photonic Materials and Device Lab (PMDL) is constantly seeking out new optical materials and photonic device innovations that can impact a broad range of applications, ranging from information technology, to renewable energy, to infrared optics.  

The ARPA-E MOSAIC program is focused on creating more efficient (> 30%) solar panels by combining standard silicon panels for diffuse light collection (labeled as 1-Sun sheet in the figure below) and high efficiency concentrated photovoltaic arrays for the direct sunlight (know as direct normal insolation or DNI).  Key optical design elements include a cylindrical lens concentrator in one direction and a waveguide sheet concentrator in the other direction as shown in the schematic.  This work is also done under subcontract to Sharp Laboratories of America and started in January 2016.   

 

Soft Nano-Photonic Systems

Date Published: June 27, 2016

College of Optical Sciences Research

Optical tweezer apparatus for colloidal nanoparticle manipulation.

Nano-photonics is the study of how light interacts with objects smaller than its wavelength. It forms the basis of some of the last decade’s revolutionary progress in photonics such as super-resolution imaging, optical cloaking, and optical biosensing. While nano-photonic devices are most often implemented in hard materials using semiconductor-processing methods, these approaches can be limited in compatibility with biological materials or complex three-dimensional designs.

Assistant Professor Euan McLeod is working on developing novel nano-photonic systems from building blocks dispersed in soft colloidal materials. This approach is compatible with biological systems, and can be harnessed to fabricate three-dimensional structures. Current application areas of interest include microscopic bio-imaging, biomedical sensors, and photonic metamaterials.