Strong magnetic field effect on above-barrier transport in Pb-p-HgCdTe Schottky barriers

Due to large difference in effective masses of light and heavy holes it is usually supposed that the above-barrier current in Schottky barriers on p-type semiconductor is controlled only by the heavy holes. However, in real structures, there is an additional potential barrier caused by a oxide layer at interface. For typical values of thickness and height of a barrier its tunnel transparency for light holes can be higher by three order of magnitude than that for heavy holes. Due to such separative role of insulator layer one can expect that the current is manly a contribution of light holes. To clear up this problem the investigation of transport in a magnetic field is used as a key experiment in this work. The pronounced magnetic field effect for heavy holes in investigated Pb-p-HgCdTe Schottky barriers is expected only at extremely strong magnetic fields B>10 T within the framework of both diode and diffusion mechanism of transport. At the same time experimentally more than twofold decrease in saturation current is observed even at B=0.5 T at any orientation of magnetic field. The studies performed for HgCdTe with different Kane's gap and at different temperatures show that the magnitude of magnetic field effect is uniquely determined by the ratio of light hole cyclotron energy to a thermal energy. However the magnitude of effect exceeds considerably the prediction of the simple theory and the experimental magnetic field dependencies of a saturation current do not follow the simple exponential falling predicted for thermionic current. The reason of this discrepancy remains a mystery.Comment: 18 pages, 6 figure

Electric field induced strong localization of electrons on solid hydrogen surface: possible applications to quantum computing

Two-dimensional electron system on the liquid helium surface is one of the leading candidates for constructing large analog quantum computers (P.M. Platzman and M.I. Dykman, Science 284, 1967 (1999)). Similar electron systems on the surfaces of solid hydrogen or solid neon may have some important advantages with respect to electrons on liquid helium in quantum computing applications, such as larger state separation $\Delta E$, absence of propagating capillary waves (or ripplons), smaller vapor pressure, etc. As a result, it may operate at higher temperatures. Surface roughness is the main hurdle to overcome in building a realistic quantum computer using these states. Electric field induced strong localization of surface electrons is shown to be a convenient tool to characterize surface roughness.Comment: 4 pages, 3 figure

The first professor headed the department of obstetrics and gynecology of Saratov State Medical University—professor N.M. Kakushkin (to the 150th anniversary)

The article presents the data concerned biography of professor N. M. Kakushkin. His scientific and practical contribution to the development of native medical science and organization of department of Obstetrics and Gynecology in Imperial Nicolas University (Saratov) have been outlined in the article

The application of OLAP technology in the automated risk assessment system for oil and gas fields

The article shows the advantages of using OLAP technology in the engineering of fields' development and its application in the automated risk assessment system

Academic V.I. Skvortsov (Dedicated to the 130-th Anniversary of His Birth)

In the article are presented biographic data about professor V. I. Skvortsove, reflecting his scientific and practical contribution to the development of domestic pharmacology and toxicology, and to the organization of opening of the higher female medical education in Sarato

The application of OLAP technology in the automated risk assessment system for oil and gas fields

The article shows the advantages of using OLAP technology in the engineering of fields' development and its application in the automated risk assessment system