Time filter

Source Type

Dubna, Russia

Gazizov I.M.,Institute for Physico Technical Problems | Zaletin V.M.,Dubna University | Kukushkin V.M.,Institute for Physico Technical Problems | Khrunov V.S.,Institute for Physico Technical Problems
Semiconductors | Year: 2011

The current response of a TlBr detector to 137Cs γ-ray radiation has been studied in the dose-rate range 0.033-3.84 Gy/min and within the voltage range 1-300 V; the detectors are based on pure and doped TlBr crystals grown from the melt by the Bridgman-Stockbarger method. The mass fraction of Pb or Ca introduced into the TlBr crystals was 1-10 ppm for Pb and 150 ppm for Ca. The current response of nominally undoped TlBr samples was nearly linear over two decades of studied dose rates. Deep hole levels associated with cationic vacancies Vc - determine the dependence of the current response on the voltage in the high electric fields. The parameters of the carriers' transport μτ are determined. The TlBr crystals grown in vacuum and in the bromine vapor exhibit a large mobility-lifetime product of 4.3 × 10-4 and 6.4 × 10-5 cm2V-1, respectively. The value of μτ is in the range (4-9) × 10-5 cm2V-1 for crystals doped with a divalent cation. © 2011 Pleiades Publishing, Ltd.

Gazizov I.M.,OAO Institute of Physical Technical Problems | Zaletin V.M.,Dubna University | Kukushkin V.M.,OAO Institute of Physical Technical Problems | Kuznetsov M.S.,OAO Giredmet | Lisitsky I.S.,OAO Giredmet
Semiconductors | Year: 2012

The kinetics of the photocurrent response in doped and undoped TlBr samples subjected to irradiation with γ-ray photons from a 137Cs source with the dose rate 0. 033 to 3. 84 Gy/min are studied. The crystals were grown by the directional crystallization of the melt method using the Bridgman-Stockbarger technique. The Pb impurity mass fraction introduced into the doped TlBr crystals was 1-10 ppm and amounted to 150 ppm for the Ca impurity. The crystals were grown in a vacuum, in bromine vapors, in a hydrogen atmosphere, and in air. Decay of the photocurrent is observed for extrinsic semiconductor crystals doped with bivalent cations (irrespective of the growth atmosphere), and also for crystals grown in hydrogen and crystals grown in an excess of thallium. The time constant of photocurrent decay τ amounted to 30-1400 s and was proportional to resistivity. It is shown that the current response can be related to photolysis in the TlBr crystals during irradiation with γ-ray photons. The energy of hole traps responsible for a slow increase in the photo-current has been estimated and found to be equal to 0. 6-0. 85 eV. © 2012 Pleiades Publishing, Ltd.

Bening V.E.,Russian Academy of Sciences | Korolev V.Y.,Russian Academy of Sciences | Savushkin V.A.,Dubna University | Zeifman A.I.,Russian Academy of Sciences
AIP Conference Proceedings | Year: 2015

In the paper we consider asymptotic deficiencies of some estimators based on the samples with random sizes. The case of the Poisson distribution is investigated. © 2015 AIP Publishing LLC.

Perepelkin E.E.,Moscow State University | Sadovnikov B.I.,Moscow State University | Inozemtseva N.G.,Dubna University
Journal of Statistical Mechanics: Theory and Experiment | Year: 2015

A derivation of the first Vlasov equation as a well-known Schrödinger equation for the probabilistic description of a system and families of the classic diffusion equations and heat conduction for the deterministic description of physical systems was inferred. A physical meaning of the phase of the wave function which is a scalar potential of the probabilistic flow velocity is demonstrated. Occurrence of the velocity potential vortex component leads to the Pauli equation for one of the spinar components. A scheme for the construction of the Schrödinger equation solution from the Vlasov equation solution and vice-versa is shown. A process of introduction of the potential to the Schrödinger equation and its interpretation are given. The analysis of the potential properties gives us the Maxwell equation, the equation of the kinematic point movement, and the equation for movement of the medium within electromagnetic fields. © 2015 IOP Publishing Ltd and SISSA Medialab srl.

Shukrinov Y.M.,Dubna University | Azemtsa-Donfack H.,University of South Africa | Rahmonov I.R.,Umarov Physical Technical Institute | Botha A.E.,University of South Africa
Low Temperature Physics | Year: 2016

We found that the coupled system of Josephson junctions under external electromagnetic radiation demonstrates a cascade of parametric instabilities. These instabilities appear along the IV characteristics within bias current intervals corresponding to Shapiro step subharmonics and lead to charging in the superconducting layers. The amplitudes of the charge oscillations increase with increasing external radiation power. We demonstrate the existence of longitudinal plasma waves at the corresponding bias current values. An essential advantage of the parametric instabilities in the case of subharmonics is the lower amplitude of radiation that is needed for the creation of the longitudinal plasma wave. This fact gives a unique possibility to create and control longitudinal plasma waves in layered superconductors. We propose a novel experiment for studying parametric instabilities and the charging of superconducting layers based on the simultaneous variation of the bias current and radiation amplitude.

Discover hidden collaborations