[en] Ferroelectric solutions Pb(Tisub(x)Zrsub(1-x))Osub(3) when Ti content constitutes 30, 35, 40, 44 and 50% in the range of hydrostatic pressures up to 40 kbar and quasihydrostatic pressures up to 80 kbar in the temperature range from +20 to +150 deg C have been studied. Measurements of dielectric permeability (epsilon) and spontaneous polarization (Ps) depending on pressure at different constant temperatures from +20 to +150 deg C are made. The detected anomalies of epsilon and Psub(s) are explained in the framework of physical notions on domain reorientations under pressure. For all the compositions studied phase p-T-diagrams are built, coordinates of ternary points detected are found, the coefficients are dT/dp. An untiferroelectric phase, existing under conditions of high pressures above 30 kbar for solid solutions Pb(TiZr)O₃ with Ti content above 30% is detected. Spatial diagram ''composition-pressure-temperature'' is plotted

[en] Dose and temperature dependences of anion defect accumulation in MgO crystals irradiated with protons have been investigated. It is shown that under high ionizing irradiation of MgO non- shock generations of Frenkel anion pairs is possible. The nonshock generation of anion defects is related to radiationless decay of complex electron excitations arising in proton tracks

No abstract available

[en] The temperature dependence of T₁ spin-lattice relaxation time on ⁵¹V, ⁶⁹Ga, ⁷¹Ga and Knight shift on ⁵¹V and ²⁹Si nuclei in polycrystalline V₃Si, V₃Ga, V₃Ge and in the monocrystal V₃Si in normal state is investigated. For V₃Si and V₃Ga a rapid growth (T₁T)^-1 is observed with temperature decrease while for V₃Ge the maximum (T₁T)^-1 at T approximately equal to 60 K has been found. The temperature dependence peculiarities have been discussed on the basis of theoretical models available and zone structure calculations for A-15 compounds. The T₁ anisotropy and possibility of its experimental discovery are considered. Anisotropic contribution in (T₁T)^-1 and contributions of d states of different symmetries into the electron state density at the Fermi level are estimated for V₃Si from T₁ measurements

No abstract available

[en] Observation of galvanomagnetic waves in indium caused by carrier drift in a superposed electric field is reported. Experiments have shown the wave propagation to be of a unidirectional character. Characteristic ime of attenuation for the investigated sample (a approximately 4 cm, rho sub(300)/rho sub(T→0) approximately 4x10⁵) is about 5s. Increase in temperature from 1.4 K to 4.2 K resulted in a higher wave attenuation, which is associated with growth (25 fold) of resistance for both the life time of excitations and drift current induced in the sample decrease. Thus, the presence of direct current can essentially change the electrodynamic properties of specific metal

[en] To study effect of tin alloying on a value of I_c critical current density in bulky sintered specimens of PbMo₆S₈, a possibility for preparation of Pb_1-xSn_xMo₆S₈ solid solutions was studied in the temperature range from 500 to 1150 deg C, their temperatures of superconducting transition T_c were measured as well as temperature dependences of upper critical field H_c2 and conductivity, lattice parameters. Observed nonlinear, and, in some cases, nonmonotonous character of concentration dependences T_c and (dH_c2/dT)_Tc is connected with disorder influence due to alloying defects, and considerable increase of I_c (4.2 K) in solid solutions up to values ∼ 5x10⁹ A/m² in 1T field and ∼ 4x10⁸ A/m² in 13T field - with strengthening of vortex lattice pinning at grain boundaries

No abstract available

[en] The nonlinear absorption of the CO₂ laser irradiation in indium antimonide is investigated by the method of two orthogonal beams. The calculation is made which explains the technique of calculating constants of two-photon absorption (TPA) from the experimental data. Results of experiments show that a significant contribution in the induced absorption of the ΔI₃ probing beam except TPA and the absorption on nonequilibrium holes created by pumping radiation in the process of TPA is made by the absorption from deep mixture centres changed by the pumping beam. The role of the latter mechanism depends on the moment of measuring ΔI₃ within the limits of laser pulse and on the level of crystal alloying. The increase in the level of alloying leads to the reduction in the contribution of this mechanism. The obtained values of TPA constants for two crystals with different electron concentrations in the conductivity zone (InSbn₀=2.4x10¹⁶cm^-3 and n₀=2.5x10¹⁷cm^-3) which is connected with the alteration of filling states in the conductivity zone

No abstract available