arXiv subjects

M. V. Sadovskii

Publications and source records attributed to M. V. Sadovskii.

94 records · Page 6Linked to original sources

arXiv1994

Ginzburg-Landau Expansion and Physical Properties of Odd-Gap Superconductors

Ginzburg-Landau expansion is derived for superconductors with the gap-function odd over $k-k_{F}$. It is shown that in this odd-gap case Ginzburg-Landau coefficients possess an additional dependence on the pairing coupling constant which leads to the appropriate dependence of the physical properties. Non-magnetic impurities influence the odd-gap pairing in a significant way and the mechanism of this influence is quite different from that predicted by the usual theory of "dirty" superconductors. In particular this is reflected in an anomalous behavior of the upper critical field $H_{c2}$ slope close to $T_{c}$. We also derive the complete temperature dependence of $H_{c2}$ for the odd-gap case.

cond-mat↗

arXiv1993

Temperature Dependence of the Upper Critical Field in High-Temperature Superconductors: Localization Effects

It is shown that the anomalous temperature dependence of the orbital part of the upper critical field $H_{c2}$ observed for epitaxially grown films of high-temperature superconductor $Bi-Sr-Cu-O$ (in wide temperature interval) can be satisfactorily explained by the influence of localization effects in two-dimensional (quasi-two-dimensional) case.

cond-mat↗

arXiv1993

On the Theory of "Odd"-Pairing Superconductors

We consider the model of superconducting pairing with the energy gap function which is odd over $k-k_{F}$.\ In this case superconductivity is possible even in the presence of an arbitrarily large point-like repulsion between electrons,\ which is attractive for the theory of high-temperature superconductors.\ We discuss mainly a model pairing interaction for which the BCS equations can be solved exactly,\ allowing the complete analysis of the interplay of the usual (``even'') and ``odd'' pairing,\ depending on the coupling constant.\ We also show that the normal impurities (disorder) lead to a rapid degradation of the ``odd'' pairing,\ which is even more rapid than in case of magnetic impurities in traditional superconductors.

cond-mat↗

arXiv1993

Impurities in "Odd-Pairing" Superconductors

We present the results of theoretical analysis of normal impurities effects in superconductors with the gap being an odd function of k-k_{F}. This model proposed by Mila and Abrahams leads to the possibility of pairing in the presence of arbitrarily strong short-range repulsion between electrons and may be applied to high-Tc oxides.However, we demonstrate that normal impurities lead to rather strong suppression of this type of pairing, which is actually stronger than in the case of magnetic impurities in traditional superconductors. Relative stability of high-Tc cuprates to disordering makes this model a rather unlikely candidate for the pairing mechanism in these systems.

cond-mat↗