A5036273857- Metamaterials and Metasurfaces Applications
- Terahertz technology and applications
- Plasmonic and Surface Plasmon Research
- Advanced Antenna and Metasurface Technologies
- Millimeter-Wave Propagation and Modeling
- Antenna Design and Analysis
- Superconducting and THz Device Technology
- Microwave Engineering and Waveguides
- Photonic and Optical Devices
- Photonic Crystals and Applications
- Optical Coatings and Gratings
- Thermal Radiation and Cooling Technologies
- Energy Harvesting in Wireless Networks
- Spectroscopy and Laser Applications
- Near-Field Optical Microscopy
- Strong Light-Matter Interactions
- Orbital Angular Momentum in Optics
- Gold and Silver Nanoparticles Synthesis and Applications
- Physics of Superconductivity and Magnetism
- Radio Wave Propagation Studies
- Electromagnetic Scattering and Analysis
- Optical Wireless Communication Technologies
- Luminescence Properties of Advanced Materials
- Semiconductor Lasers and Optical Devices
- Quantum Dots Synthesis And Properties
The University of Adelaide
2020-2025
Los Alamos National Laboratory
2015-2024
Center for Integrated Nanotechnologies
2015-2024
Jet Propulsion Laboratory
2020
Space Information Laboratories (United States)
2020
North Carolina State University
2020
Aalto University
2020
The University of Western Australia
2020
UCLA Health
2020
Sandia National Laboratories
2016
Polarization is one of the basic properties electromagnetic waves conveying valuable information in signal transmission and sensitive measurements. Conventional methods for advanced polarization control impose demanding requirements on material attain only limited performance. Here, we demonstrate ultrathin, broadband, highly efficient metamaterial-based terahertz converters that are capable rotating a linear state into its orthogonal one. Based these results create metamaterial structures...
The impedance matching in metamaterial perfect absorbers has been believed to involve and rely on magnetic resonant response, with a direct evidence from the anti-parallel directions of surface currents metal structures. Here we present different theoretical interpretation based interferences, which shows that two layers structure are linked only by multiple reflections negligible near-field interactions or resonances. This is further supported out-of-phase derived at interfaces resonator...
We demonstrate THz metamaterials exhibiting either amplitude control, via carrier injection or depletion in the active semiconductor substrate frequency photoexcitation of carriers into semiconducting materials incorporated sub-wavelength metamaterial structure.
We report on the application of scanning near-field optical microscopy for terahertz imaging. demonstrate a spatial resolution 150 nm 2.0 THz pulses. Our experiments show feasibility submicron imaging biologic tissues cell level or investigation individual semiconductor devices.
We present a novel approach of antireflection coating using metamaterials. It dramatically reduces the reflection and greatly enhances transmission near specifically designed frequency over wide range incidence angles for both transverse magnetic electric polarizations. A classical interference mechanism is identified through analytical derivations numerical simulations. elucidates that tailored magnitude phase waves reflected transmitted at boundaries metamaterial are responsible antireflection.
Planar electric split ring resonator (eSRR) metamaterials and their corresponding inverse structures are designed characterized computationally experimentally utilizing finite element modeling THz time domain spectroscopy. A complementary response is observed in transmission. Specifically, for the eSRRs a decrease transmission at resonance whereas display an increase The frequency dependent effective complex dielectric functions extracted from experimental data and, combination with...
We design and implement a multipixel spatial modulator for terahertz beams using active metamaterials. Our first-generation device consists of 4×4 pixel array, where each is an array subwavelength-sized split-ring resonator elements fabricated on semiconductor substrate, independently controlled by applying external voltage. Through transmission experiments, we show that the has uniform modulation depth around 40% across all pixels, negligible crosstalk, at resonant frequency. This can...
Abstract We demonstrate a broadband, polarization independent, wide-angle absorber based on metallic metasurface architecture, which accomplishes greater than 90% absorptance in the visible and near-infrared range of solar spectrum exhibits low absorptivity (emissivity) at mid- far-infrared wavelengths. The complex unit cell consists eight pairs gold nano-resonators that are separated from ground plane by thin silicon dioxide spacer. Our experimental measurements reveal high-performance...
During the past decades, major advances have been made in both generation and detection of infrared light; however, its efficient wavefront manipulation information processing still encounter great challenges. Efficient fast optoelectronic modulators spatial light are required for mid-infrared imaging, sensing, security screening, communication navigation, to name a few. However, their development remains elusive, prevailing methods reported so far suffered from drawbacks that significantly...
We present the design, numerical simulations and experimental measurements of terahertz metamaterial absorbers with a broad flat absorption top over wide incidence angle range for either transverse electric or magnetic polarization depending on incident direction. The absorber unit cell consists two sets structures resonating at different but close frequencies. overall spectrum is superposition individual components becomes significant bandwidth. results are in excellent agreement simulations.
Metasurfaces with actively tunable features are highly demanded for advanced applications in electronic and electromagnetic systems. However, realizing independent dual-tunability remains challenging requires more efforts. In this paper, we present an active metasurface where the magnitude frequency of resonant absorption can be continuously independently tuned through application voltage biases. Such a is accomplished at microwave frequencies by combining varactor-loaded high-impedance...
In this Letter we present resonance properties in terahertz metamaterials consisting of a split-ring resonator array made from high temperature superconducting films. By varying the temperature, observed efficient metamaterial switching and frequency tuning with some features not revealed before. The results were well reproduced by numerical simulations using experimentally measured complex conductivity film. We developed theoretical model that explains features, which takes into account...
We demonstrated giant optical activity using a chiral metamaterial composed of an array conjugated bilayer metal structures. The metamaterials were further integrated with photoactive inclusions to accomplish wide tuning range the through illumination near-infrared light. strong chirality observed in our results negative refractive index, which can also be well controlled by excitation.
Arbitrary control of terahertz (THz) waves remains a significant challenge although it promises many important applications. Here, method to tailor the reflection and scattering THz in an anomalous manner by using 1‐bit coding metamaterials is presented. Specific sequences result various far‐field patterns, ranging from single beam two, three, numerous beams, which depart obviously ordinary Snell's law reflection. By optimizing sequences, wideband thin film metamaterial with extremely low...
Harnessing light for modern photonic applications often involves the control and manipulation of polarization phase. Traditional methods require a combination multiple discrete optical components, each which contributes to specific functionality. Here, plasmonic metasurfaces are proposed that accomplish simultaneous phase transmitted light. Arbitrary spatial field distribution direction can be obtained. The multifunctional validated by demonstrating broadband near‐perfect anomalous...
Solar energy promises a viable solution to meet the ever-increasing power demand by providing clean, renewable alternative fossil fuels. For solar thermophotovoltaics (STPV), high-temperature absorbers and emitters with strong spectral selectivity are imperative efficiently couple radiation into photovoltaic cells. Here, we demonstrate refractory metasurfaces for STPV tailored absorptance emittance characterized in-situ measurements, featuring thermal stability up at least 1200 C. Our...
Abstract Controlled charge flows are fundamental to many areas of science and technology, serving as carriers energy information, probes material properties dynamics 1 a means revealing 2,3 or even inducing 4,5 broken symmetries. Emerging methods for light-based current control 5–16 offer particularly promising routes beyond the speed adaptability limitations conventional voltage-driven systems. However, optical generation manipulation currents at nanometre spatial scales remains basic...
We demonstrate optical switching of electrically resonant terahertz planar metamaterials fabricated on ErAs/GaAs nanoisland superlattice substrates. Photoexcited charge carriers in the shunt capacitive regions constituent elements, thereby modulating response metamaterials. A recovery time 20 ps results from fast carrier recombination