Vladimir S. Epov

Effect of magnetic field on the sensitivity of PbSnTe:In films to THz radiation

The variation of conductivity and charge-carrier concentration in PbSnTe:In films with magnetic-field strength in samples exposed to illumination with free-electron-laser radiation at wavelengths λ=138.5 μm and 200 μm and, in addition, to illumination in the fundamental absorption band of the material, was examined. At certain magnetic-field strengths, measured dependences exhibited distinct maxima; the emergence of those maxima was interpreted within the concept of a quasi-continuous energy spectrum of traps for charge carriers in the band-gap of PbSnTe:In.

The conductivity switch effect in PbSnTe:In thin films

The Hall effect measurement data in the case of switching the conduction by electric field is presented in the paper. It is shown that a sharp decrease of both carrier mobility and density occurs at switch moment. Possible mechanisms of the switch are discussed.

Temperature-dependent photocurrent decay in PbSnTe:In films

The temperature-dependent photocurrent decay in PbSnTe:In films has been studied in the interval of temperatures T≈20-30 K at each implemented temperature having been stabilized accurate to ΔT≈0.01 K. The time constant of the process, whose value in the examined temperature interval proved to be ranging from ≈1.0 s to ≈200 s, was measured. The behavior displayed by the curve τ(T) is discussed on the assumption that, in the examined interval of temperatures, a ferroelectric transition occurs in PbSnTe:In.

Current relaxation in PbSnTe:In in a strong magnetic field

Current change dynamics in the injection regime out of contacts and limitations by spatial charge at a fast (about 0.1 sec.) magnetic field turn on and off, strength to 4 T, were investigated in PbSnTe:In film-based structures at T=4.2 K. Peculiarities of current relaxation are discussed within the model that implies the presence of traps levels, distributed over energy, in the PbSnTe:In band gap.

Effect of magnetic field on injection currents in PbSnTe:In films

In the present paper, we consider the influence of magnetic fields B ≤ 2 T on the electric current in thin PbSnTe:In films, kept at Т=4.2 K, with prevailing injection of charge carriers out of contacts and space-charge-controlled limitation of the current. Data for various orientations of the field B with respect to the direction of the current in the film plane, and also data on transient currents, are reported. The data obtained are analyzed within the theory of space-charge-limited electric currents and with due regard for ferroelectric properties of PbSnTe:In.

Kinetics of transient photocurrents in PbSnTe∶In films exposed to THz radiation

The results of an experimental study of the kinetics of photocurrent rise in PbSnTe∶In films exposed at T=4.2 K to free-electron laser radiation of wavelengths 68, 123, and 205 µm are reported. The obtained data are analyzed within the model of space-charge-limited injection currents that flow in a material with electron traps.

Anisotropy of current-voltage characteristics in PbSnTe:In film structures

In the present work, we propose a model to describe the anisotropy of current-voltage characteristics in PbSnTe:In films at low temperatures under electron injection out of contacts. The model is developed considering the ferroelectric properties of PbSnTe:In. Data on the temperature dependence of the anisotropy are reported.

Effect of magnetic field on the current-voltage characteristics of PbSnTe:In films

Transport of charge carriers in Pb1-xSnxTe:In films at helium temperatures in regimes dominated by charge-carrier injection out of contacts is discussed. Data illustrating the effect of constant magnetic field on the injection currents are reported. Possible mechanisms of observed phenomena are discussed.

Field Injection in Pb0.76Sn0.24 Te: in Films with Superimposed Magnetic Field

In the present study, low-temperature electronic transport in Pb1-xSnxTe:In films with prevailing contact injection of charge carriers was examined. Data concerning the influence of magnetic field on the injection currents, and also on the transient currents observed following turn-on and turn-off of the field are reported. Possible mechanisms of observed phenomena are discussed.