2D VAN HOVE SUPERCONDUCTORS WITH WEAK AND STRONG-COUPLINGS

F. Parvin, A.K. M.A. Islam, F. N. Islam

Abstract


The critical temperature (Tc) and the isotope coefficient (α) of two-dimensional van Hove superconductors have been analyzed. The phonon induced superconductors with both weak and strong couplings are considered. For weak coupling, the variation of Tc and α as a function of average phonon frequency, ωD, for three sets of pairing potential, V, shows that α decreases at nearly same rate with the increase of ωD; but Tc increases with increasing ωD but at different rates for different V. For strong coupling, the variation of Tc and α shows that smaller band width produces desirable results that are consistent with observation.

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References


J. Labbe and J. Bok, Europhys- Lett., 3 (1987) 1225; Labbe, Phys. Scri. T, 29 (1989) 82; R. Combescot and J. Labbe, Phys. Rev. B, 38 (1988) 262.

J. Friedel, J. Phys, 48 (1987) 1787; J. Phys.: Condens. Matter, 1 (1989) 7757.

G.M. Eliashberg and Zh. Eksp. Teor. Fiz, 38 (1960) 996; Sov. Phys. JETP, 11 (1960) 696.

R. Szczesniak, M. Mierzejewski, J. Zielinski, and P. Entel, Solid State Communi., 117 (2001) 369.

F. Parvin, M. Sc. Thesis, Rajshahi University, Bangladesh, (2002).

P.B. Allen, B. Mitrovic, in : H. Ehrenreich, F. Seitz and D. Turnbull (Eds.), Solid State Physics, 37, Academic, New York (1982)1.

A.N. Das, J. Lahiri and S. Sil, Physica C, 294 (1998) 97.


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