G. Kozłowski

Ac loss minimum in type II superconductors

Abstract Theoretical predictions with respect to a minimum in the ac losses in type II superconductors are compared with experimental results on Nb-50% Ti and Nb-10% Mo. Extensions of the theory are suggested to explain the deviations.

“Mixed” state in type II ferromagnetic superconductor

Abstract We have studied a ferromagnetic superconductor having both a magnetic domain structure of the Kittel-type and a laminar structure of the normal regions. Our phenomenological approach is a combination of Ginzburg-Landau theory for superconductivity and the microscopic theory of ferromagnetism. Calculations of the thermodynamical potential and a comparison with Meissner and normal states offer the possibility to predict conditions for the crystal thickness and/or the absolute value of the magnetization vector at which the “mixed” state can exist.

Magnetic induction vector in a ferromagnetic superconductor with domain structure

Abstract Using a phenomenological approach, the dependence of the magnetic induction vector on the position in the domain structure of a ferromagnetic superconductor is given.

Spin waves and magnetocaloric effect in a two-sublattice antiferrimagnet

Abstract The magneticaloric effect in the stable antiferrimagnetic phase of a two-sublattice uniaxial antiferrimagnet is studied on the basis of the spin wave theory.

Surface impedance of antiferromagnetic superconductors

Abstract The dependence of the low-frequency surface impedance on the types of magnetic configurations induced by an external field in an antiferromagnetic superconductor is given.