相关论文: Analysis of Bessel Beam Generation Using MetaMater…
Terahertz communications is a promising modality for future short-range point-to point wireless data transmission at rates up to terabit per second. A milestone towards this goal is the development of an integrated transmitter and receiver…
We present and study theoretically a new design approach for obtaining wide angle, highly efficient, all-dielectric metasurfaces. As a concrete example we focus on optimizing flat beam deflector for both the infra-red and visible spectral…
Imaging systems operating in the terahertz part of the electromagnetic spectrum are in great demand because of the distinct characteristics of terahertz waves in penetrating many optically-opaque materials and providing unique spectral…
Sub-wavelength graphene structures support localized plasmonic resonances in the terahertz and mid-infrared spectral regimes. The strong field confinement at the resonant frequency is predicted to significantly enhance the light-graphene…
We generate conical second-harmonic radiation by transverse excitation of a two-dimensional annular periodically-poled nonlinear photonic structure with a fundamental Gaussian beam. We show that these conical waves are the far-field images…
Exploration of optical non-linear response of graphene predominantly relies on ultra-short time domain measurements. Here we propose an alternate technique that uses frequency modulated continuous wavefront optical fields, thereby probing…
We experimentally analyze a Bessel beam produced with a conical mirror, paying particular attention to its superluminal and diffraction-free properties. We spatially characterized the beam in the radial and on-axis dimensions, and verified…
Plasmon oscillations have been intensively studied for more than forty years in conventional two-dimensional electron gas systems in order to find new alternatives to the vacuum devices based on the Smith-Purcell effect in the far-infrared…
Typically, photonic waveguides designed for nonlinear frequency conversion rely on intuitive and established principles, including index guiding and band gap engineering, and are based on simple shapes with high degrees of symmetry. We show…
The development of responsive metamaterials has enabled the realization of compact tunable photonic devices capable of manipulating the amplitude, polarization, wave vector, and frequency of light. Integration of semiconductors into the…
Bessel beams are renowned members of a wide family of non-diffracting (propagation-invariant) fields. We report on experiments showing that non-diffracting fields are also immune to diffusion. We map the phase and magnitude of structured…
Fingerprint spectral response of several materials with terahertz electromagnetic radiation indicates that terahertz technology is an effective tool for sensing applications. However, sensing few nanometer thin-film of dielectrics with much…
This paper presents a study on performance optimization and resonant frequency modification of terahertz detectors by the use of hyper-hemispherical silicon superstrate lenses. The detectors are patch-TeraFETs, i.e., field-effect…
Phased arrays, commonly used in IEEE 802.11ad and 5G radios, are capable of focusing radio frequency signals in a specific direction or a spatial region. Beamforming achieves such directional or spatial concentration of signals and enables…
We demonstrate that a near-field microwave microscope based on a transmission line resonator allows imaging in a substantially wide range of frequencies, so that the microscope properties approach those of a spatially-resolved impedance…
Large surface area applications such as high-efficiency > 26% solar cells require surface patterning with 1-10 micrometers periodic patterns at high fidelity over 1-10 cm^2 areas (before up scaling to 1 m^2) to perform at, or exceed, the…
Metamaterials made of periodic arrangements of electric permittivity and magnetic permeability and arrays of resonators can provide optic properties unexperienced in conventional materials, such as negative refractive index which can be…
We developed a Bessel light sheet fluorescence microscopy (LSFM) system to enable high-speed, wide-field intra-vital imaging of zebrafish and other thick biological samples. This system uses air objectives for the convenient mounting of…
Current wireless systems are experiencing unprecedented pressure that could be relieved by shifting carrier frequencies towards the terahertz spectrum. Yet, components are required to enable spectrally efficient communications at such high…
It has been recently shown that especially engineered light beams have the remarkable ability to propagate along curved trajectories in vacuum. Current methods for generating accelerating beams use phase modulators and lenses leading to…