Specific Heat Jump at Tc of High Tc Superconductors: Effect of Van Hove Singularity
Tóm tắt
In the BCS framework, exact expressions for the ratio between the jump in the specific heat at T
c
and the normal phase specific heat are derived within the Van Hove singularity scenario. Analytical results are obtained for an isotropic s-wave and anisotropic d-wave pairing symmetries. Graphical solutions of the ratio as functions of ω
D
/T
c
and E
F
/T
c
, where ω
D
is the cutoff energy and E
F
is the Fermi energy, show significant deviations from the BCS value of 1.43.
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