U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by:

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 51 - 75 of 105

Low-loss Metasurface Optics down to the Deep Ultraviolet

August 9, 2020
Author(s)
Cheng Zhang, Shawn M. Divitt, Qingbin Fan, Wenqi Zhu, Amit Agrawal, Yanqing Lu, Ting Xu, Henri Lezec
Metasurfaces, planar arrays of subwavelength electromagnetic structures that collectively mimic the functionality of much thicker conventional optical elements, have been demonstrated at frequencies ranging from the microwave up to the visible. Here, we

Broadband detection of multiple spin and orbital angular momenta via dielectric metasurface

July 26, 2020
Author(s)
Si Zhang, Pengcheng Huo, Wenqi Zhu, Cheng Zhang, Peng Chen, Mingze Liu, Lu Chen, Henri Lezec, Amit Agrawal, Yanqing Lu, Ting Xu
Light beams carrying spin angular momentum (SAM) and orbital angular momentum (OAM) have created novel opportunities in the areas of optical communications, imaging, micromanipulation and quantum optics. However, complex optical setups are required to

Chiroptical response of aluminum nano-crescents at ultraviolet wavelengths

April 21, 2020
Author(s)
Matthew S. Davis, Wenqi Zhu, Jared Strait, Jay K. Lee, Henri Lezec, Steve Blair, Amit Agrawal
Manipulation of plasmon modes at ultraviolet wavelengths using engineered nanophotonic devices allows for the development of high-sensitivity chiroptical spectroscopy systems. We present here a framework for the fabrication and characterization of Al based

Photonic spin-multiplexing metasurface for switchable spiral phase contrast imaging

March 10, 2020
Author(s)
Pengcheng Huo, Cheng Zhang, Wenqi Zhu, Mingze Liu, Song Zhang, Si Zhang, Lu Chen, Henri Lezec, Amit Agrawal, Yanqing Lu, Ting Xu
As the two most representative operation modes in an optical imaging system, bright-field imaging and phase contrast imaging can address different dimensionalities of an object. Developing a miniature and low-cost system capable of switching between these

Ultra-compact visible light depolarizer based on dielectric metasurface

February 4, 2020
Author(s)
Yilin Wang, Wenqi Zhu, Cheng Zhang, Qingbin Fan, Lu Chen, Henri Lezec, Amit Agrawal, Ting Xu
With rapid development towards shrinking the size of traditional photonic systems such as cameras, spectrometers, displays and illumination systems, there is an urgent need for high performance and ultra-compact functional optical elements. The large

Microscopic origin of the chiroptical response of optical media

October 11, 2019
Author(s)
Matthew S. Davis, Wenqi Zhu, Jay K. Lee, Henri Lezec, Amit Agrawal
The potential for enhancing the optical activity of natural chiral media using engineered nanophotonic components has been central in the quest towards developing next-generation circular-dichroism spectroscopic techniques. Through confinement and

Ultrathin Wetting Layer-Free Plasmonic Gold Films

October 3, 2019
Author(s)
Robert Lemasters, Cheng Zhang, Manoj Manjare, Wenqi Zhu, Junyeob Song, Sergei Urazhdin, Henri Lezec, Amit Agrawal, Hayk Harutyunyan
Ultrathin gold films are attractive for plasmonic and metamaterial devices, thanks to their useful optical and optoelectronic properties. However, deposition of ultrathin continuous Au films of few nanometer thickness is challenging and generally requires

Revisiting the Photon-Drag Effect in Metal Films

August 2, 2019
Author(s)
Jared H. Strait, Glenn E. Holland, Wenqi Zhu, Cheng Zhang, Bojan R. Ilic, Amit K. Agrawal, Domenico Pacifici, Henri J. Lezec
The photon-drag effect, the rectified current in a medium induced by conservation of momentum of absorbed or redirected light, is a unique probe of the detailed mechanisms underlying radiation pressure. We revisit this effect in gold, a canonical Drude

Ultrafast Optical Pulse Shaping using Dielectric Metasurfaces

May 2, 2019
Author(s)
Shawn M. Divitt, Wenqi Zhu, Cheng Zhang, Henri Lezec, Amit Agrawal
Simultaneous control of individual frequency-comb lines, and their modulation at the repetition-rate of an ultrafast laser represents the ultimate limit of optical pulse shaping. Remarkable progress in mode-locked lasers and chirped pulse amplifiers

Broadband generation of photonic spin-controlled arbitrary accelerating light beams in the visible

February 13, 2019
Author(s)
Qingbin Fan, Wenqi Zhu, Yuzhang Liang, Pengcheng Huo, Cheng Zhang, Amit Agrawal, Kun Huang, Xiangang Luo, Yanqing Lu, Chengwei Qiu, Henri Lezec, Ting Xu
Bending light along arbitrary curvatures is a captivating and popular notion, triggering unprecedented endeavors in achieving quasi-diffraction-free propagation along a curved path in free-space. Much effort has been devoted to achieving this goal in

Robust Extraction of Hyperbolic Metamaterial Permittivity using Total Internal Reflection Ellipsometry

June 20, 2018
Author(s)
Cheng Zhang, Nina Hong, Chengang Ji, Wenqi Zhu, Xi Chen, Amit K. Agrawal, Zhong Zhang, Tom E. Tiwald, Stefan Schoeche, James N. Hilfiker, L. Jay Guo, Henri J. Lezec
Hyperbolic metamaterials are optical materials characterized by highly anisotropic effective permittivity tensor components having opposite signs along orthogonal directions. The techniques currently employed for characterizing the optical properties of