Ferromagnetic semiconductor nanostructures—future spintronics

The review analyzes and summarizes the principal results of research on the magnetic properties of ferromagnetic semiconductor nanostructures. These materials possess unique physical properties, which attracts great attention both from the scintific and practical viewpoints. The review shows that group A_IIB_VI and A_IIIB_V ferromagnetic semiconductors, as well as group IV elemental semiconductors hold the greatest promise for spintronic applications.     

Solution of the Cauchy problem for a system of integrodifferential equations of viscoelasticity

Existence and uniqueness of the solution of the Cauchy problem is proved for a system of integrodifferential equations of the hereditary theory of viscoelasticity. A method of constructing an approximate solution is proposed. An estimate of the error of the approximate solution is presented.     

Polymer Electrolytes for Lithium Power Sources

Russian Journal of Electrochemistry -     

A new type of magnetoplastic effects in linear amorphous polymers

A new type of magnetoplastic effects in polymers is revealed. This effect cannot be explained by the reorientation of macromolecular units that possess a magnetic susceptibility anisotropy. It is shown that the joint action of magnetic and electric fields and the rotational mobility of side groups in macromolecules are factors of crucial importance in changing the plasticity of polymers in pulsed magnetic fields.     

Thermally induced paramagnetism of spiropyran salts

An increase in the effective magnetic moments and linewidths in ESR spectra caused by the presence of crystallization water molecules in crystals of tris(oxalato)chromium(III) complexes with spiropyran cations Sp⁺ was found. Dehydration (rehydration) of crystals causes a reversible decrease (increase) in thermally induced paramagnetism of Sp⁺. Thermally induced paramagnetism of crystals appears in the compounds synthesized in oxygen atmosphere but is not found in the compounds synthesized under argon atmosphere. The contributions of chromium oxalates and thermally excited spiropyran molecules to the magnetization were separated using ESR spectroscopy. The enthalpies of the biradical states of some types of spiropyran cations in crystals were determined.     

Structural defects in molecular crystals based on heterospin copper complexes

Jumplike changes in the microhardness, sample dimensions, and parameters of the EPR spectrum were observed in molecular Cu(hfac)₂L^Et crystals undergoing a phase transition. Defects that appear upon plastic deformation (e.g., dislocations) and paramagnetic defects were revealed. The latter defects are likely breaks in polymer chains and can serve as spin marks for investigating the magnetic state of the crystal lattice.     

Calculation of the nonlinear viscoelastic oscillations of an antivibration layer

It is proposed to use a viscoelastic layer to protect equipment against vibration. The principal quadratic theory of hereditary viscoelasticity is used as the physical relation between the forces and displacements. The solutions obtained for the integrodifferential vibration equation make it possible to minimize the displacements and accelerations of the protected equipment.Moscow Institute of Electronic-Machine Building. Translated from Mekhanika Polimerov, No. 2, pp. 321–326, March–April, 1972.