National Technology & Engineering Solutions of Sandia, LLC

Sandia Corporation

Ucl Business Plc

University of Exeter

Igal Brener

Michael B Sinclair

Salvatore Campione

Sheng Liu

Xiaoyu Miao

Brandon Passmore

Eric A Shaner

Ganapathi Subramanian Subramania

Polina Vabishchevich

Young Chul Jun

Qiming Li

John Dalton Williams

Paul J Resnick

Darren W Branch

Paul Gilbert Clem

David Bruce Burckel

George T Wang

John F Klem

Michael C Wanke

Richard Douglas Averitt

Conrad D James

Christian Lew Arrington

Ting S Luk

Michael Goldflam

Jennifer K Sigman

John F O'Hara

Jeremy Benjamin Wright

Larry K Warne

Abul Kalam Azad

Lorena I Basilio

William L Langston

D Bruce Burckel

Xomalin Guaiuli Peralta

Evgenya Smirnova

Aaron J Pung

Surendra K Ravula

Martyn Hill

Rosemary June Boltryk

Oleg Mitrofanov

Stavroula Foteinopoulou

Alexander Benz

Raktim Sarma

Nche Tumasang Fofang

A theoretically perfectly absorbing photoconductive all-dielectric metasurface is provided. This metasurface can improve the efficiency and performance of ultrafast photoconductive switches and detectors. In an embodiment, the metasurface is incorporated in photoconductive THz switches or detectors. In embodiments, the metasurface is constituted by a network of gallium arsenide resonators. Each resonator supports two degenerate and critically coupled magnetic dipole modes. Simultaneous excitation of these two modes leads to theoretically close-to-perfect optical absorption near the resonant wavelength.

Photoconductive metasurface-based ultrafast device

An apparatus and method are provided for generating harmonic light from a pump beam that is impinged on a metasurface comprising a plurality of all-dielectric resonator bodies. A multiple quantum well structure formed in each resonator body includes asymmetric coupled quantum wells having intersubband transition frequencies that couple to Mie resonances of the resonator bodies.

Efficient ultrathin all-dielectric nonlinear optical device

Dielectric resonators provide a building block for the development of low-loss resonant metamaterials because they replace lossy ohmic currents of metallic resonators with low-loss displacement currents. The spectral locations of electric and magnetic dipole resonances of a dielectric resonator can be tuned by varying the resonator geometry so that desired scattering properties are achieved.

Optical devices enabled by vertical dielectric Mie resonators

Tunable filters can use Fano metasurface designs having extremely narrow transmission bands. The Fano metasurface can comprise dielectric or semiconductor materials and can produce transmission bands with quality factors well in excess of 1000&#x2014;at least a factor of 50 greater than typical metamaterial-based infrared resonances. Numerical simulations of these metasurfaces show that the spectral position of the passband can be changed by slightly changing the position of a small dielectric perturbation block placed within the near-field of the resonator by using simple electromechanical actuation architectures that allow for such motion. An array of independently tunable narrowband infrared filters can thereby be fabricated that only requires deep-subwavelength motions of perturbing objects in the resonator's near-field.

Rapidly tunable, narrow-band infrared filter arrays

An array of dielectric resonators is formed on a substrate. Each resonator includes an active medium having an optical transition that is operative in a process of photodetection or photoemission. The active media each include a quantum well multilayer. The dielectric resonators in the array are each dimensioned to provide a resonance that lies substantially at the frequency of the optical transition.

Active optical device enabled by dielectric metamaterials

An array of dielectric resonators is formed on the substrate of an optoelectronic device. Each resonator includes an active medium having an optical transition that is operative in a process of photodetection or photoemission. The dielectric resonators in the array are each dimensioned to provide a resonance that lies substantially at the frequency of the optical transition.

Optoelectronic apparatus enabled by dielectric metamaterials

A method of nonlinear wavelength generation uses a nonlinear optical medium. An input flux of pump energy is applied to one or more dielectric optical resonators. Each resonator has an optical cavity comprising the nonlinear optical medium. Each resonator has at least one Mie resonance that is excited by the input flux of pump energy. The pump energy causes the generation of converted light containing at least one converted component having a frequency attainable only through a non-linear process.

Nonlinear optical frequency conversion using metamaterial arrays

A structure for broadband light funneling comprises a two-dimensional periodic array of connected ultrasubwavelength apertures, each aperture comprising a large sub-aperture that aids in the coupling of the incoming incident light and a small sub-aperture that funnels a significant fraction of the incident light power. The structure possesses all the capabilities of prior extraordinary optical transmission platforms, yet operates nonresonantly on a distinctly different mechanism. The structure demonstrates efficient ultrabroadband funneling of optical power confined in an area as small as &#x2dc;(&#x3bb;/500), where optical fields are enhanced, thus exhibiting functional possibilities beyond resonant platforms.

Broadband light funneling in ultrasubwavelength channels having periodic connected unfilled apertures

A mid-infrared tunable metamaterial comprises an array of resonators on a semiconductor substrate having a large dependence of dielectric function on carrier concentration and a semiconductor plasma resonance that lies below the operating range, such as indium antimonide. Voltage biasing of the substrate generates a resonance shift in the metamaterial response that is tunable over a broad operating range. The mid-infrared tunable metamaterials have the potential to become the building blocks of chip based active optical devices in mid-infrared ranges, which can be used for many applications, such as thermal imaging, remote sensing, and environmental monitoring.

Mid-infrared tunable metamaterials

A new monolithic resonator metasurface design achieves ultra-high Q-factors while using only one resonator per unit cell. The metasurface relies on breaking the symmetry of otherwise highly symmetric resonators to induce intra-resonator mixing of bright and dark modes (rather than inter-resonator couplings), and is scalable from the near-infrared to radio frequencies and can be easily implemented in dielectric materials. The resulting high-quality-factor Fano metasurface can be used in many sensing, spectral filtering, and modulation applications.

High quality-factor fano metasurface comprising a single resonator unit cell

A photonic apparatus includes a metamaterial resonator array overlying and electromagnetically coupled to a vertically stacked plurality of quantum wells defined in a semiconductor body. An arrangement of electrical contact layers is provided for facilitating the application of a bias voltage across the quantum well stack. Those portions of the semiconductor body that lie between the electrical contact layers are conformed to provide an electrically conductive path between the contact layers and through the quantum well stack.

Tuneable photonic device including an array of metamaterial resonators

The efficiency of a photovoltaic cell is enhanced by light trapping using Mie-scattering nanostructures. In one embodiment, an array of nanocylinders is formed on the front surface of a silicon film to enhance forward scattering into the film, and an array of nanocylinders is formed on the back surface to enhance backscattering so that more light is absorbed within the silicon film. In an alternate embodiment, a mirror layer is formed on the back surface of the silicon film to reflect light within the film back toward the front-surface nanocylinder array.

Photovoltaic cell with light trapping for enhanced efficiency

A wavelength-tunable, depletion-type infrared metamaterial optical device is provided. The device includes a thin, highly doped epilayer whose electrical permittivity can become negative at some infrared wavelengths. This highly-doped buried layer optically couples with a metamaterial layer. Changes in the transmission spectrum of the device can be induced via the electrical control of this optical coupling. An embodiment includes a contact layer of semiconductor material that is sufficiently doped for operation as a contact layer and that is effectively transparent to an operating range of infrared wavelengths, a thin, highly doped buried layer of epitaxially grown semiconductor material that overlies the contact layer, and a metallized layer overlying the buried layer and patterned as a resonant metamaterial.

Electrically tunable infrared metamaterial devices

A multicolor photonic crystal laser array comprises pixels of monolithically grown gain sections each with a different emission center wavelength. As an example, two-dimensional surface-emitting photonic crystal lasers comprising broad gain-bandwidth III-nitride multiple quantum well axial heterostructures were fabricated using a novel top-down nanowire fabrication method. Single-mode lasing was obtained in the blue-violet spectral region with 60 nm of tuning (or 16% of the nominal center wavelength) that was determined purely by the photonic crystal geometry. This approach can be extended to cover the entire visible spectrum.

Multicolor photonic crystal laser array

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Albuquerque, NM, United States of America

Igal Brener