Phase Diagrams of Thin Disordered Films Based on HTSC YBa2Cu3O7 – x in External Magnetic Fields

Physics of the Solid State - An unusual decrease in the slope of the upper critical field near Tc0 at a gradual increase in the ion implantation dose has been experimentally observed in narrow...     

Dual-wavelength stimulated emission from a double-layer Cd x Hg1 − x Te structure at wavelengths of 2 and 3 μm

Dual-wavelength stimulated emission from a double-layer Cd _x Hg_{1 ? x} Te heterostructure optically pumped by a pulsed Nd:YAG laser at temperatures T = 77–150 K is reported. The emission spectral lines have been observed at wavelengths λ₁ ～ 2 μm and λ₂ ～ 3 μm. Emission spectra recorded at different temperatures are presented.     

Stimulated emission from optically excited CdxHg1−xTe structures at room temperature

Main requirements for the optimization of Cd_xHg_1?xTe (MCT) structures with a view to increasing the wavelength of stimulated emission under optical pumping are discussed. A 2–2.5 μm stimulated emission from optimized MCT structures is observed experimentally at room temperature. The measured values of the gain in the active medium amount to 50 cm^?1 at a 2 μm emission wavelength.     

Ac magnetic field screening by high-Tc superconductor films and single-crystals

A method is proposed to measure the screening efficiency of an ac magnetic field by superconducting films with the use of a strip line as an ac magnetic field source capable of operating within a broad frequency range. The dependence of the efficiency of ac magnetic field screening by YBCO films and single-crystal BiSrCaCuO on temperature and the frequency of magnetic field oriented perpendicular to the sample plane has been studied in the 10⁴–10⁹-Hz range. This relation is shown to depend substantially on the technique used in the film fabrication. Fiz. Tverd. Tela (St. Petersburg) 39, 228–230 (February 1997)     

DViN—Stationary setup for identification of explosives

A stationary system for the identification of hidden explosives was developed and constructed at the Joint Institute for Nuclear Research (JINR). The results of the examination of the system, as well as the operation principle of the system and design of the main elements are presented. The text was submitted by the authors in English.     

DViN-2 stationary inspection complex

A DViN-2 stationary inspection complex has been designed and manufactured for identifying hidden explosives and drugs. The identification of hidden substances is based on the method of tagged neutrons. The source of the tagged neutron beam, which has an energy of 14.1 MeV produced in the reaction d + t → α + n, is a portable neutron generator with a built-in 9-channel silicon α detector. The DViN-2 makes it possible to identify hidden explosives and drugs with a mass of from 100 g to 50 kg in objects with dimensions from 50 to 400 mm in all three directions. The results of 76 experiments testify to the high efficiency of the DViN-2 in regards to identifying hidden explosives and drugs and it has a rather low probability of false actuations: the probability of identifying explosives and drugs is 94%, and that of false alarms rate is 3%. The time it takes to identify hidden substances, depending on their mass and the thickness of the shielding material layer, is 3–7 min for an average neutron beam intensity into a solid angle of 4π of 2 × 10⁷s^?1.     

Properties of Josephson junctions in the nonuniform field of ferromagnetic particles

Experimental and theoretical studies of ferromagnet-superconductor hybrid systems consisting of a Josephson junction placed in the nonuniform field of submicron ferromagnetic particles are reviewed.