A5038726404- Plasmonic and Surface Plasmon Research
- Metamaterials and Metasurfaces Applications
- Advanced Antenna and Metasurface Technologies
- Advanced Fiber Laser Technologies
- Photonic Crystals and Applications
- Photonic and Optical Devices
- Terahertz technology and applications
- Laser-Matter Interactions and Applications
- Orbital Angular Momentum in Optics
- Antenna Design and Analysis
- Millimeter-Wave Propagation and Modeling
- Advanced Photonic Communication Systems
- Nanowire Synthesis and Applications
- Nonlinear Optical Materials Studies
- Gold and Silver Nanoparticles Synthesis and Applications
- Optical Coatings and Gratings
- Semiconductor Quantum Structures and Devices
- Thermal Radiation and Cooling Technologies
- Magneto-Optical Properties and Applications
- Semiconductor Lasers and Optical Devices
- Laser Material Processing Techniques
- Silicon Nanostructures and Photoluminescence
- Ga2O3 and related materials
- Quantum optics and atomic interactions
- Optical Polarization and Ellipsometry
University of Maryland, College Park
2022-2024
Sandia National Laboratories
2017-2022
National Institute of Standards and Technology
2022
Center for Integrated Nanotechnologies
2018-2022
National Institute of Standards
2022
Friedrich Schiller University Jena
2021
National Technical University "Kharkiv Polytechnic Institute"
2020
Lomonosov Moscow State University
2009-2019
Russian Quantum Center
2018
Moscow State University
2009-2015
We demonstrate experimentally ultrafast all-optical switching in subwavelength nonlinear dielectric nanostructures exhibiting localized magnetic Mie resonances. employ amorphous silicon nanodisks to achieve strong self-modulation of femtosecond pulses with a depth 60% at picojoule-per-disk pump energies. In the pump-probe measurements, we reveal that can be governed by pulse-limited 65 fs-long two-photon absorption being enhanced factor 80 respect unstructured film. also show undesirable...
Optical metasurfaces are regular quasi-planar nanopatterns that can apply diverse spatial and spectral transformations to light waves. However, no longer adjustable after fabrication, a critical challenge is realise technique of tuning their optical properties both fast efficient. We experimentally an ultrafast tunable metasurface consisting subwavelength gallium arsenide nanoparticles supporting Mie-type resonances in the near infrared. Using transient reflectance spectroscopy, we...
All-dielectric metasurfaces, two-dimensional arrays of subwavelength low loss dielectric inclusions, can be used not only to control the amplitude and phase optical beams, but also generate new wavelengths through enhanced nonlinear processes that are free from some constraints dictated by use bulk materials. Recently, high quality factor (Q) resonances in these metasurfaces have been revealed utilized for applications such as sensing lasing. The origin stems interference two nanoresonator...
A frequency mixer is a nonlinear device that combines electromagnetic waves to create at new frequencies. Mixers are ubiquitous components in modern radio-frequency technology and widely used microwave signal processing. The development of versatile mixers for optical frequencies remains challenging: such devices generally rely on weak processes and, thus, must satisfy phase matching conditions. In this work, we utilize GaAs-based dielectric metasurface demonstrate an concurrently generates...
Light-emitting sources and devices permeate every aspect of our lives are used in lighting, communications, transportation, computing, medicine. Advances multifunctional "smart lighting" would require revolutionary concepts the control emission spectra directionality. Such might be possible with new schemes regimes light–matter interaction paired developments light-emitting materials. Here we show that all-dielectric metasurfaces made from III–V semiconductors embedded emitters have...
Toroidal moment is an electromagnetic excitation that lies outside the familiar picture of electric and magnetic multipoles. It has recently been a topic intense research in fields nanophotonics metamaterials due to its weakly radiating nature ability confine energy. Among extensive studies on toroidal moments their applications, high quality factor (Q) resonances have experimentally realized only very limited set geometries wavelengths. In this study, we demonstrate metasurface consisting...
Terahertz (THz) photoconductive devices are used for generation, detection, and modulation of THz waves, they rely on the ability to switch electrical conductivity a subpicosecond time scale using optical pulses. However, fast efficient switching with high contrast has been challenge, because majority photoexcited charge carriers in do not contribute photocurrent due recombination. Here, we improve efficiency network electrically connected nanoscale GaAs resonators, which form perfectly...
Nonlinear optics is a well-established field of research that traditionally relies on the interaction light with macroscopic nonlinear media over distances significantly greater than wavelength light. However, recently emerged optical metasurfaces provides novel platform for studying phenomena in planar geometries. introduce new functionalities to extending them beyond perturbative regimes harmonic generation and parametric frequency conversion, being driven by mode-matching, resonances,...
The color of light is a fundamental property electromagnetic radiation; as such, control the frequency cornerstone modern optics. Nonlinear materials are typically used to generate new frequencies, however use time-variant systems provides an alternative approach. Utilizing metasurface that supports high-quality factor resonance, we demonstrate rapidly shifting refractive index will induce conversion confined in nanoresonator meta-atoms. We experimentally observe this and develop...
We demonstrate all-optical switching of high quality factor quasibound states in the continuum resonances broken symmetry GaAs metasurfaces. By slightly breaking nanoresonators, we enable leakage protected bound (BICs) to free space that results sharp spectral with factors ∼500. tune resulting quasi-BIC ultrafast optical pumping at 800 nm and observe a 10 blue shift resonance pump fluences less than 100 μJ cm−2. The is achieved an time scale (<2.5 ps) caused by refractive index...
Perfect absorption of light by an optically thin metasurface is among several remarkable optical functionalities enabled nanophotonics. This functionality can be introduced into optoelectronic devices structuring active semiconductor-based element as a perfectly absorbing all-dielectric metasurface, leading to improved properties while simultaneously providing electrical conductivity. However, delicate combination geometrical and material parameters required for perfect absorption,...
Saturable optical elements lie at the cornerstone of many modern systems. Regularly patterned quasi-planar nanostructures—metasurfaces—are known to facilitate nonlinear processes. Such subwavelength semiconductor nanostructures can potentially serve as saturable components. Here we report on intensity-dependent reflectance femtosecond laser pulses from metasurfaces with Mie-type modes, caused by absorption saturation. Arrays GaAs nanocylinders magnetic dipole resonances in spectral vicinity...
Ultrafast all-optical switching using Mie resonant metasurfaces requires both on-demand tunability of the wavefront light and ultrafast time response. However, devising a mechanism that has high contrast between its “on” “off” states without compromising speed is challenging. Here, we report design tunable metasurface achieves this behavior. Our approach utilizes diffractive array semiconductor resonators support dipolar quadrupolar resonances. By balancing strengths dipole quadrupole...
Femtosecond-scale polarization state shaping is experimentally found in optical response of a plasmonic nanograting by means time-resolved Stokes polarimetry. Simultaneous measurements the parameters as function time reveal remarkable alteration inside single femtosecond pulse reflected from crystal due to excitation time-delayed polarization-sensitive surface plasmons with highly birefringent Fano-type spectral profile. Time-dependent depolarization, indicating sub-130-femtosecond change...
We report on the results of theoretical and experimental studies photoluminescense silicon nanocrystals in proximity to plasmonic modes different types. In studied samples, type mode is determined by filling ratio a one-dimensional array gold stripes which covers thin film with quartz substrate. analyze extinction, photoluminesce spectra decay kinetics show that incident emitted light coupled corresponding mode. demonstrate modification extinction under transition from wide narrow stripes....
Perfect optical absorption occurs in a metasurface that supports two degenerate and critically-coupled modes of opposite symmetry. The challenge designing perfectly absorbing for desired wavelength material stems from the fact satisfying these conditions requires multi-dimensional optimization often with parameters affecting resonances non-trivial ways. This problem comes to fore semiconductor metasurfaces operating near bandgap wavelength, where intrinsic varies significantly. Here we...
Single photon emitters (SPEs) in hexagonal boron nitride (hBN) are elementary building blocks for room-temperature on-chip quantum photonic technologies. However, fundamental challenges, such as slow radiative decay and nondeterministic placement of the emitters, limit their full potential. Here, we demonstrate large-area arrays plasmonic nanoresonators (PNRs) Purcell-induced SPEs by engineering emitter-cavity coupling enhancing emission. Gold-coated silicon pillars with an alumina spacer...
A time-resolved study of the transverse magneto-optic Kerr effect at femtosecond timescales. When 45-fs laser pulses are reflected from an iron grating under external magnetic field, surface-plasmon polaritons with magnetization-dependent dispersion excited; and as these decay in time, they affect pulse profile. This work opens possibility manipulating fields.
Optical metasurfaces were suggested as a route for engineering advanced light sources with tailored emission properties. In particular, they provide control over the directionality, which is essential single-photon and LED applications. Here, we experimentally study from metasurface composed of III-V semiconductor Mie-resonant nanocylinders integrated quantum dots (QDs). Specifically, focus on manipulation directionality spontaneous QDs due to excitation different magnetic quadrupole...
Femtosecond-scale magnetic field-controlled shaping of 200 fs laser pulses reflected from a one-dimensional magnetoplasmonic crystal is experimentally demonstrated. Magnetic field-induced modification the pulse shape revealed by measuring second-order intensity correlation function (CF) femtosecond sample. The sign contribution to CF reversed within pulse. Such temporal attributed Fano-type surface plasmon spectral response under magnetization sample in Voigt configuration.
We experimentally demonstrate resonantly enhanced nonlinear optical processes such as 2nd-, 3rd-, and 4th-harmonic generations, sum-frequency generation, four-wave mixing processes, etc., in the visible near-IR using GaAs dielectric metasurfaces.