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Macroscopic magnetic measurements were performed on superconducting alloys. From the results of these experiments microscopic parameters namely the energy gap and the vortex creation energy could be calculated. Their dependence on the additive material content (or on the GL-parameter) was determined. It was shown that the BCS and the GLAG theory are applicable for small-κ superconductors in wide temperature interval.

Characterizing the energetic, electric and magnetic interactions occurring at the superconductivity by means of the method of extensive and intensive parameters, the total entropy density of a general superconductor has been determined. The resulting formula contains all possible superconducting effects and describes them separately with an additive term for each. The fundamental equation obtained can be applied for the individual special superconducting states by taking into consideration the particular terms corresponding to them.

Some considerations are given about the Onsager-Kohler relations with respect to the linear dependence or independence of the magnetoresistivity (MR) effects. The symmetry properties of the heat conductivity tensor are investigated to elucidate a possible experimental proof of the Onsager-Kohler relations.

Based on the measurement of the magnetic characteristics of In−Bi, In−Tl, In−Pb, Sn−Bi and Sn−Sb superconducting alloys it was stated that the phase transition type I→ type II superconductivity is of higher than second order. Comparing the experimental data with the Lifshitz’s theory it is shown that the addition falls between the values of 0.63 and 0.77.

Analytical expressions are given which describe the dependence of the critical temperature, of the critical magnetic fields and of the GL parameter on the concentration of the alloying material, characterizing the phase transition within the superconducting state in good agreement with the experiments.

A model is proposed for the exact calculation of the specific electrical conductivity of a semiconducting slab between two circular metallic electrodes. The assumed mixed boundary conditions and the derived dual integral equations lead to a Fredholm integral equation of the second type for infinite slabs. The latter is solved numerically and the results are discussed in terms of a correction function plotted against the ratio of the slab thickness to the electrode radius in the range of 0.01–10. A resistor network has been used to verify the calculations. A good agreement has been found with previously published results in some range of thickness-radius function.

The phase transition “type I to type II superconductivity” was investigated theoretically by thermodynamic methods in the framework of the GLAG formalism. The conditions of the forming of the vortex lattice structure were determined and the features of the transition described. It was shown that the order parameter becomes space dependent in a periodic way during the phase transition. The critical value of the GL parameter and the range of the wave number belonging to the magnetic vortices which appear at the transition were given.

In a one dimensional model the possibility of synchronization of the flux line system to the randomly distributed pinning centres is shown. The result yields direct summation without threshold in the very dilute case.

Thermodynamic description of the superconducting states has been performed. The thermodynamic interactions and the extensive and intensive parameters are determined. It is shown that the use of magnetic moment as an extensive parameter results in a contradiction.

Investigation of galvanomagnetic effects was carried out in the temperature range of 1.5–350 K. The samples were made ofn- andp-type PhS, cut off in different orientations and rotated in the magnetic field.

A model of the flux creep state has been constructed on the base of a force proportional to the vortex movement. Non-equilibrium vortex density is induced by the effect of external electric current introduced into type II superconductors. Its equalization is an exponentially time dependent process. This generates a state of dynamic flux creep studied in this paper.

Basic phenomenological parameters of superconductivity have been determined by a thermodynamic and a quantum-mechanical method and expressed with microscopic parameters.

Our earlier result, representing the dependence of critical temperature of superconducting transition on the concentration of dia- and paramagnetic impurities is applied to the case whenT c approaches absolute zero owing to impurities. We calculated the rate of spin flip scatteringsΔΓ s0 for an electron at the Fermi surface, when either the scattering processes or the change in the Fermi surface topology have a dominant role. The expressions obtained were verified by a comparison with experimental data and by numerical estimation.

The problem of the Volta-effect was theoretically dealt with byC. Eckart (on the basis of Fermi statistics), byC. A. Domenicali (with irreversible thermodynamical methods), and by others, all these investigations, however, referred to a stationary case. The aim of the present paper is to investigate the non-stationary irreversible process giving rise to the Volta-effect. For want of numerical data, our conclusions are of qualitative character.

Some of the modern experiments in nuclear and solid state physics [1] require extremely low temperatures (T≪1° K). Temperatures of this kind can be satisfactorily produced by the process of adiabatic demagnetization. The present paper is discussing the thermodynamical relations on the basis of which the refrigerating process is effected. First the computation is performed for an ideal case and then also for the real refrigerating cycle.

The transport coefficients of Si single crystals were calculated assuming ellipsoid equienergetic surfaces. The results were checked by means of longitudinal Hall effect and anisotropy investigations. Hot electron measurements reflected the role of the interactions arising, determined the value of the critical field and produced a detectable size effect. The effects were measured in the [100], [110] and [111] planes and the dependence of the longitudinal Hall voltage on the angle between the directions of the electric and magnetic field was plotted.

We calculate the dependence of the transition temperature and its derivative with respect to pressure on the concentration of both paramagnetic and diamagnetic impurities. It is shown that the assumption of a Lifshitz singularity in the density of normal single-electronic states results in a good agreement of theoretical predictions with experimental data.

The stability of stationary thermodynamic states will be examined by means of a variation principle. The Euler-Lagrange equations, existing as the necessary condition of the extremum, provide the total stationary balance equation of the entropy production where — beside the spontaneous entropy production — the source terms also appear. This method is equally suitable for describing stable and unstable stationary states, moreover it contains the total stationariness. It will be shown that the stability of the stationary equilibrium is secured by the positive definite character of the conductivity matrix. Applying this principle for the interaction of homogeneous bodies we get the simplest model and stability criteria for stationariness.