SUPERCONDUCTIVITY IN LOW DIMENSIONAL SYSTEMS WITH DIFFERENT ENERGY DISPERSIONS
DOI:
https://doi.org/10.24193/subbphys.2018.11Keywords:
Superconductivity, low dimensional systems, graphene, linear dispersion, constant dispersion.Abstract
We analyzed the possibility for occurrence of superconductivity in low dimensional systems, taking into consideration a linear and a constant dispersion law for the electronic excitations. Using a mean field BCS-like model we calculate the zero temperature energy gap, the critical temperature, and the Gelikman-Kresin ratio. In the case of graphene with a linear dispersion the coupling strength should exceed a critical value. Taking realistic parameters it was shown that the occurrence of the superconducting state is not possible. We find out an opposite situation for a two-dimensional system with a constant dispersion.References
J.Bardeen, L.N.Cooper, J.R.Schrieffer, Phys. Rev., 108, 1175 (1957)
J.G.Bednorz, K.A.Müller, Z. Phys. B, 64, 189 (1986)
P.Monthoux, A.Balatski, D.Pines, Phys. Rev. B, 46, 14803 (1992)
I.Grosu, M.Crisan, Phys.Rev. B, 49, 1269 (1994)
C.M.Varma, Z.Nussinov, W.von Saarloos, Phys. Repts., 361, 267 (2002)
I.Grosu, I.Tifrea, M.Crisan, J. Supercond., 11, 339 (1998)
S.Fujita, S.Godoy, “Quantum Statistical Theory of Superconductivity”, Plenum Press, New York (1996)
M.Crisan, I.Tifrea, D.Bodea, I.Grosu, Phys. Rev. B, 72, 184414 (2005)
A.K.Geim, K.S.Novoselov, Nature Mater, 6, 183 (2007)
A.H.Castro Neto, F.Guinea, N.M.R.Peres, K.S.Novoselov, A.K.Geim, Rev. Mod. Phys., 81, 109 (2009)
B.M.Ludbrook et al., PNAS 112, 11795 (2015)
N.B.Kopnin, E.B.Sonin, Phys.Rev.Lett., 100, 246808 (2008)
A.L.Fetter, J.D.Walecka, “Quantum Theory of Many-Particle Systems”, McGraw-Hill, New York (1971)
T.J.Peltonen, R.Ojajärvi, T.T.Heikkilä, arXiv: 1805.01039
B.Krunavakarn, P.Udomsamuthirun, S.Yoksan, I.Grosu, M.Crisan, J.Supercond., 11, 271 (1998)
P.B.Allen, B.Mitrovic, “Solid State Physics”, edited by H.Ehrenreich, F.Seitz, D.Turnbull, Academic, New York (1982)
D.C.Mattis, M.Molina, Phys. Rev. B, 44, 12565 (1991)
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2018 Studia Universitatis Babeș-Bolyai Physica
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
