A5054411293- Semiconductor Quantum Structures and Devices
- Luminescence Properties of Advanced Materials
- Quantum optics and atomic interactions
- Photonic and Optical Devices
- Strong Light-Matter Interactions
- Semiconductor Lasers and Optical Devices
- Inorganic Fluorides and Related Compounds
- Quantum and electron transport phenomena
- Spectroscopy and Quantum Chemical Studies
- Spectroscopy and Laser Applications
- Photonic Crystals and Applications
- Solid-state spectroscopy and crystallography
- Random lasers and scattering media
- Ion-surface interactions and analysis
- Atomic and Subatomic Physics Research
- Optical and Acousto-Optic Technologies
- Semiconductor materials and devices
- Photorefractive and Nonlinear Optics
- Material Properties and Applications
- bioluminescence and chemiluminescence research
- Atomic and Molecular Physics
- Silicon Nanostructures and Photoluminescence
- Magnetism in coordination complexes
- Optical properties and cooling technologies in crystalline materials
- Chemical Thermodynamics and Molecular Structure
St Petersburg University
2007-2017
Institute of Physics
2007-2011
State Optical Institute named after SI Vavilov
1973-2004
Central Research Institute
1975
Central Research Institute for Machine Building
1975
The characteristics of luminescence, excited by long wavelength radiation, in various solid systems (ionic crystals, activated rare earth elements; semiconducting crystals with absorbed layers sensitizer dye; green leaves plants) have been investigated. It was found that all cases studied the emission arises as a result cooperative processes, owing to interactions two or more states. role excitation phenomenon sensitization photochemical and photophysical processes is pointed out.
Photoluminescence and reflectivity spectra of a high-quality InGaAs/GaAs quantum well structure reveal series ultranarrow peaks attributed to the confined exciton states. The intensity these decreases as function temperature, while linewidths demonstrate complex peculiar behavior. At low pumping widths all remain quite narrow $(<0.1\phantom{\rule{0.28em}{0ex}}\mathrm{meV})$ in whole temperature range studied, 4--30 K. stronger pumping, linewidth first increases then drops down with rise....
The dynamics of electron-spin coherence in $\mathrm{GaAs}∕{\mathrm{Al}}_{0.34}{\mathrm{Ga}}_{0.66}\mathrm{As}$ quantum wells has been studied experimentally by a pump-probe Kerr rotation technique. dephasing time was measured to be $10\phantom{\rule{0.3em}{0ex}}\mathrm{ns}$ for 17-nm well containing about ${10}^{10}\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}2}$ background electrons at temperature $1.8\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. Decrease the electron density causes...
We propose a method of spatial modulation inhomogeneous broadening quantum-well excitonic resonance based on local generation defects produced by focused ion beam. The is applied to fabrication diffraction grating in single InGaAs/GaAs structure irradiating the sample with beam 35-keV He+ ions exposure doses <1012 cm-2. spectrum resonant such narrower than that reflectivity and decreases much faster increasing temperature. A proposed model formation diffractive response scattering...
The effect of irradiation by 30‐keV Ga + and 35‐keV He ions (in relatively small doses) on the excitonic reflectivity spectra single InGaAs/GaAs quantum‐well structures is studied. It found that results in decreasing intensity broadening resonances for all doses. shown these changes are not related to a decrease exciton transition oscillator strength and, therefore, irradiation‐induced destruction states, but can be rather ascribed common cause, namely, inhomogeneous proportional exposure...
Picosecond kinetics of polarized resonant photoluminescence (PL) HH excitons in the GaAs/AlGaAs superlattices is studied an external magnetic field. The measurements were made real time using a streak camera. For field aligned along heterostructure growth direction, PL exhibits oscillations degree linear polarization. are ascribed to quantum beats between sublevels optically active excitonic doublet split by plane layers, found exhibit circular These related states and inactive doublets....
The effect of external electric bias on the kinetics circularly polarized photoluminescence (PL) GaAs quantum wells (QWs) is studied experimentally. It found that a negative applied to top surface samples causes appearance slow component in decay PL circular polarization. amplitude this grows with ${U}_{\mathrm{bias}}$ and reaches nearly 100% at ${U}_{\mathrm{bias}}=\ensuremath{-}2\mathrm{V}.$ In transverse magnetic field, polarization shows oscillations related spin precession. changes...
We report on a method of creating spectrally selective diffractive optical elements based resonantly reflecting mirrors made semiconductor structures with 2D Wannier–Mott excitons. This employs strong dependence resonant reflection coefficient the inhomogeneous broadening determined by exciton scattering quantum‐well structural defects. Realization proposed addressable control excitonic resonance width includes two stages. At first stage substrate surface is exposed to an ion beam intensity...
The robustness of AlGaAs/GaAs quantum well to strong resonant excitation is studied. It was found that lowering Al concentration in barriers 3% does not influence the measured radiative linewidth exciton resonance sample at low intensities. At same time parasitic broadening by an additional illumination strongly suppressed as compared with 30% barriers.
We propose an approach to realization of all-optical logical operations based on the nonlinear dynamics ensemble two-level systems (TLSs) in a coherent photonic field. Using theoretical analysis behaviour TLS resonant field, we formulate requirements for dynamic characteristics medium suitable implementation gate. Experimental studies optical and excitonic state spectra epitaxial GaAs/AlGaAs quantum wells superlattices has allowed us conclude that their physical parameters make it possible...
Abstract Stationary and transient spectroscopy of excitonic induction is applied for measuring the rates processes controlling efficiency coherence transfer under photon‐exciton transformations in GaAs/AlGaAs structures with single quantum wells. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
We report an experimental study of the nonlinear response single GaAs/AlGaAs quantum well. It was shown that bleaching effect manifested as reversible exciton spectral lines broadening can be suppressed by additional above-barrier illumination.