On Linear Groups of Degree 2n Containing a Representation of the Special Linear Group of Degree n

Let n be an integer, n ≥ 2, and let a field P be a quadratic extension of an infinite field k. Regarding P as a k-vector space of dimension 2, we consider an n-dimensional P-vector space V as a 2n-dimensional k-vector space so the general linear group GL _n (P) acting on V is embedded in the group GL _2n (k). Let a field K be an algebraic extension of k. In this article, we determine overgroups of the special linear group SL _n (P) in the group GL _2n (K).     

Microstructure and electrical properties of SnS thin films

Thin SnS films are of interest for optoelectronics. The influence of the preparation modes on the microstructure and electrical properties of thin SnS films obtained by the hot-wall method on substrates made of pure glass and glass with a molybdenum sublayer has been investigated. It has been established that the formation of SnS films with two texture types (111) and (010) is possible on the substrates made of pure glass, depending on the mode. The resistivity and the temperature coefficient of thermoelectric power of the SnS films on glass vary in the range from 12 to 817 Ω cm and from 37 to 597 μV/K, respectively, depending on the preparation modes. The activation energy is 0.11–0.12 eV.     

Transfer Phenomena in Nd0.65Sr0.35Mn1–x FexO3 Ferrimanganites

Results of investigations of the structure and some electrical properties (the electrical conductivity and the thermoelectromotive force) of strontium-substituted neodymium ferrimanganites are presented. The study is based on the band model of charge-carrier transfer.     

On Subgroups of the General Linear Group over the Skew Field of Quaternions Which Include the Symplectic Group

Subgroups of the general linear group over the skew field of quaternions are described which include the symplectic group over some subfield of this skew field.     

Influence of thermal treatment on the microstructure and electrical and optical properties of SnS thin films

The influence of thermal treatment on the microstructure and electrical and optical properties of SnS films obtained by the “hot-wall” method has been investigated. It has been established that the thermal treatment does not lead to the formation of foreign phases in the film composition. The average film roughness after the thermal treatment increases from 10 to 20 nm. Resistivity after the thermal treatment decreases from 230 to 100 Ωcm (T = 300 K), while the temperature coefficient of thermopower increases from 40 to 330 μV K^?1. The band gap is 1.46 eV. The adsorption edge is not displaced after the thermal treatment.     

Transvection parameter sets in linear groups over associative division rings and special Jordan algebras defined by these rings

In this paper we construct a correspondence between a class of irreducible linear groups of finite degree over an associative division ring D and special Jordan rings which are defined by D. Received: 14 September 2005     

The KT-BRST Complex of a Degenerate Lagrangian System

Quantization of a Lagrangian field system essentially depends on its degeneracy and implies its BRST extension defined by sets of non-trivial Noether and higher-stage Noether identities. However, one meets a problem how to select trivial and non-trivial higher-stage Noether identities. We show that, under certain conditions, one can associate to a degenerate Lagrangian L the KT-BRST complex of fields, antifields and ghosts whose boundary and coboundary operators provide all non-trivial Noether identities and gauge symmetries of L. In this case, L can be extended to a proper solution of the master equation.