A5008075010- Glass properties and applications
- Photonic Crystals and Applications
- Photonic and Optical Devices
- Photorefractive and Nonlinear Optics
- Nonlinear Optical Materials Studies
- Gold and Silver Nanoparticles Synthesis and Applications
- Semiconductor Lasers and Optical Devices
- Quantum Dots Synthesis And Properties
- Laser Material Processing Techniques
- Phase-change materials and chalcogenides
- Plasmonic and Surface Plasmon Research
- Chalcogenide Semiconductor Thin Films
- Solid State Laser Technologies
- Advanced Fiber Laser Technologies
- Semiconductor Quantum Structures and Devices
- Radioactive element chemistry and processing
- Laser-Ablation Synthesis of Nanoparticles
- Luminescence Properties of Advanced Materials
- Surface Roughness and Optical Measurements
- Optical and Acousto-Optic Technologies
- Mineralogy and Gemology Studies
- Optical Coatings and Gratings
- Spectroscopy and Quantum Chemical Studies
- Crystal Structures and Properties
- Silicon Nanostructures and Photoluminescence
Peter the Great St. Petersburg Polytechnic University
2016-2025
St Petersburg University
1997-2023
ORCID
2021-2022
Saint Petersburg Academic University
2012-2021
Institute of Physics
1999-2018
Tampere University
2016
Physico-Technical Institute
2016
University of Eastern Finland
2015
Nello Carrara Institute of Applied Physics
2010
Institute for Microelectronics and Microsystems
2010
We observe that the temperature coefficients of electron-hole pair energies $(dE/dT)$ in PbS and PbSe quantum dots depend strongly on size dot. With decreasing coefficient lowest energy ${\mathrm{dE}}_{g}/dT$ decreases by more than an order magnitude from bulk value. The weak dependence found strong-confinement limit is expected for atomiclike levels, but has not been observed previously a semiconductor.
The controlled synthesis of PbSe nanocrystal quantum dots with narrow size distributions was achieved through phase decomposition the solid solution in a phosphate glass host. Structural characterization by electron microscopy and x-ray diffraction shows that have mean diameters between 2 15 nm. exciton Bohr radius aB=46 nm PbSe, so these provide unusual perhaps unique access to regime strong confinement. optical absorption spectra are compared predictions theoretical treatment electronic...
Soda lime glasses polarized either with an open or a blocking anode have been characterized by IR reflectance spectroscopy and combined analysis of second harmonic generation Raman imaging. The experimental results clearly show that the electrode nature influences strongly (i) thickness space charge layer, (ii) χ(2) efficiency, (iii) structural rearrangements. Besides, using theoretical models accounting for carriers' mobilities, respective influence two distinct compensation mechanisms, is...
Thermal poling of glasses induces structural and compositional modification breaks central symmetry these initially isotropic media. In spite numerous experimental data accumulated, little is known about the processes occurring in soft under this processing. We use micro-Raman technique to study formation interstitial molecular oxygen subsurface layer a soda-lime silicate glass course thermal poling. The presence O2 demonstrated cation-depleted subanodic region glass, thickness which depends...
Optical-absorption spectra of PbSe and PbS spherical quantum dots have been studied both theoretically experimentally. Exact theoretical analysis the energy optical transitions has carried out in framework four-band $\mathbf{k}\ensuremath{\cdot}\mathbf{p}$-method with full account anisotropy effects. It is demonstrated that strong bands bulk results pronounced dots, which are forbidden isotropic approximation. These anisotropy-induced clearly observed measured absorption dots.
Microdisk lasers demonstrate high performance and low threshold characteristics due to supporting of whispering gallery modes with a quality factor. One the challenging problems impeding some practical applications mode is that they have isotropic emission predominantly lying in plane cavity. In this work, we present novel method provides both enhancement laser modifies its directivity, making vertical direction favorable. Electromagnetic energy outcouples from cavity through platinum–carbon...
Ultrasmall microring and microdisk lasers with an asymmetric air/GaAs/Al0.98Ga0.02As waveguide active region based on InAs/InGaAs/GaAs quantum dots emitting around 1.3 μm were fabricated studied. The diameter D of the microrings microdisks was either 2 or 1.5 μm, inner d varied from 20% to 70% outer D. = 0.8 demonstrated a threshold pump power as low 1.8 μW at room temperature. Lasing observed up 100°C owing use providing high confinement energy both for electrons holes. Tuning spectral...
High-performance injection microdisk (MD) lasers grown on Si substrate are demonstrated for the first time, to best of our knowledge. Continuous-wave (CW) lasing in microlasers with diameters from 14 30 μm is achieved at room temperature. The minimal threshold current density 600 A/cm2 (room temperature, CW regime, heatsink-free uncooled operation) comparable that high-quality MD GaAs substrates. Microlasers silicon emit wavelength range 1320-1350 nm via ground state transition...
The nonlinear absorption properties of a glass–ceramic containing ferroelectric sodium niobate (NaNbO3) crystallites were investigated. Two- and three-photon coefficients determined using nanosecond pulsed lasers. optical power-limiting performance for light beams at 1064 532 nm was dependent on the volume fraction NaNbO3 formed during heat-treatment process.
Measurements of the third-order nonlinear refractive index, ${n}_{2},$ and two-photon absorption coefficient, ${\ensuremath{\alpha}}_{2},$ a transparent niobic silicate nanocomposite are reported. Samples with various filling factors, $f,$ sodium niobate nanocrystals were studied at 1064 nm, 800 532 nm. $Z$-scan Kerr gate techniques applied using picosecond femtosecond lasers. The response time nonlinearity was demonstrated to be smaller than 100 fs. An explanation is given for observed...
A survey of results on use semiconductor-doped glass saturable absorbers for near-infrared passively mode-locked and Q-switched solid-state lasers is presented. Nanosized semiconductor particles (quantum dots) belong to quantum confined systems where motion an electron a hole defined by the finite size nanoparticle. Dependence excitonic transition energy QDs provides possibility tune absorption glasses embedded with such wavelength specific light source. IV-VI (PbS, PbSe) are interest IR...
In this paper, the optical dispersion properties and Raman gain of sodium phosphate glasses containing niobium oxide at increasing concentrations have been systematically investigated, with aim establishing a potential enhancement its bandwidth respect to silica. A broadening higher peak (approximately 17 times) than in silica glass observed high molar content. Our findings point out that sodium–niobium–phosphate could be utilized for realization amplifiers.
We demonstrate that silver nanoisland film self-assembled on the surface of silver-containing glass in course thermal processing hydrogen is capable to detect 10-7 M concentration rhodamine 6G water using enhanced Raman spectroscopy (SERS) technique. The can be multiply restored same substrate via annealing hydrogen. showed after as much ten circles cleaning followed by annealing. proposed technique formation enables multiple usage SERS experiments.
A 31 µm in diameter microdisk laser with an InAs/InGaAs quantum dot active region has been tested the continuous‐wave regime at elevated temperatures. Lasing is achieved up to 100°C a threshold current of 13.8 mA. The emission spectrum demonstrates single‐mode lasing 1304 nm side mode suppression ratio 24 dB and dominant linewidth 35 pm.
We demonstrate that the dissolution of 10 nm metal nanoparticles localized in subsurface layer silicate glass by static electric field can be employed to alter optical density and surface profile glass–metal composite with spatial resolution 200 nm. The developed technique, which referred as imprinting (EFI), offers an attractive alternative conventional micro- nano-pattering techniques.
We fabricated silver nanoisland films and patterned using out-diffusion of from glass in the course ion-exchanged substrate annealing reducing hydrogen atmosphere. The choice conditions allows to provide prevailing formation over nanoparticles bulk glass. procedure film includes (i) silver-sodium ion exchange glass, (ii) thermal poling with a profiled anodic electrode, (iii) hydrogen. nanoislands unpoled regions on surface allowed us avoid any post-processing very fragile island 2D-patterned...
We fabricated self-assembled silver nanoisland films using a recently developed technique based on out-diffusion of from an ion-exchanged glass substrate in reducing atmosphere. demonstrate that the position surface plasmon resonance depends conditions film growth. The can be gradually shifted up to 100 nm towards longer wavelengths by atomic layer deposition titania, 3 thickness, upon film. Examination surface-enhanced Raman spectrometry showed that, spite drop spectroscopy (SERS) signal...