Weak Superconductivity

Z. Janu, F. Soukup

Investigation of magnetic properties of superconductors by  SQUID  magnetometers. The goal of our work is to understand to the magnetic properties of superconductors in the low-field region of   H-T  phase diagram. These properties are studied from temperature dependencies of   dc  magnetisation,  ac susceptibility,  M-H measurements and relaxation processes. 

Superfluidity and quantum turbulence

T. Chagovets, F. Soukup

Flow properties of superfluid He II (stability of oscillating boundary layer flow) and quantum turbulence (temporal decay of counterflow turbulence) above 1.3 K are studied using second sound attenuation technique.

Flows of rotating superfluid ³He phases and of  He II in zero temperature limit are investigated in collaboration with Finland and UK.

Experiments on high Rayleigh number cryogenic thermal convection are under preparation.

Joint Laboratory for Magnetic Studies

 J. Sebek, A. Andreev, E. Santava

The experimental equipment of the laboratory enables a study of a wide spectrum of magnetic and transport properties of solids, mainly of intermetallic compounds of the RTX, UTX, RT₂X₂, RCo₂, RCu₂, R₂T₁₇,U₂T₁₇, UFe₂ type (where R stands for rare earth, T is transition metal and X denotes p-element), of the materials modified by various substitutions, and of van Vleck paramagnets under extremal conditions and superconductors in broad temperature range 0.35-350 K, magnetic fields up to 14 T and hydrostatic pressures up to 2 GPa.

Mössbauer spectroscopy

K. Zaveta, A. Lancok

Mössbauer studies of systems that include nanoparticles of Fe compounds and alloys – nanocomposites of  SiO₂ type lattice with embedded particles of various crystallographic modifications of Fe₂O₃ or spinel structure ferrites MFe₂O₄ (where M=Co, Ni, Zn, Cd, Cu a Mn).

Nanogranullar systems prepared by controlled crystallization of amorphous (i.e., metastable)       Fe compounds produced by fast cooling processes.