The Spatial Distribution of Magnetization in a Ferromagnetic Semiconductor Thin Film
A model for the description of the distribution of magnetization across the thickness of a ferromagnetic
semiconductor film is considered. Applying a constant electric field perpendicular to the film surface
makes it possible to change the Curie temperature. The obtained formulas determine the dependence
that this distribution has on the values of the physical parameters of the film.
A theoretical model describing the spontaneous magnetization of a ferromagnetic semiconductor (InMn)As film in the presence of an external electric field directed across the film is considered. It is assumed that the ions of a manganese impurity with spin 5/2 are acceptors, have a uniform spatial distribution inside the semiconductor, and do not change their position under the action of an external field. The motion of holes with spin ½ changes their spatial distribution under the action of the field. The exchange interaction between manganese ions and holes allows the formation of magnetization that is non-uniform across the film thickness.
In particular, the existence of a piecewise continuous solution describing the presence of a phase transition boundary for magnetization inside a ferromagnetic semiconductor film is shown.
We prove the strong Suslin reciprocity law conjectured by A. B. Goncharov and describe its corollaries for the theory of scissor congruence of polyhedra in hyperbolic space. The proof is based on the study of Goncharov’s conjectural description of certain rational motivic cohomology groups of a field. Our main result is a homotopy invariance theorem for these groups.
The technique of resonance effects analysis in the quantum exchange interaction of the electron and positron flows is developed. At the framework of macroscopic quantum theory conducted a joint decision of the Schrödinger and Poisson equations for the macroscopic wave function of the electrons and positrons. Resonance effects in the quantum exchange interaction leads to selforganization of the active volume of a charged medium, and continue up to dynamic compensation of the Coulomb field and the establishment of an electron-positron mode. The calculation results of the potential distribution and the wave functions of the exchange interaction are present.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.