Anisotropy of Gap Parameter in Cuprate Superconductors

S. Prakash

The anisotropy of gap parameter in cuprate superconductors is explained in the frame work of BCS theory using two-dimensional itinerant model of conduction electrons. The BCS gap equation at T=0 is solved in the first iteration approximation. The two-dimensional electron energy bands and electron-phonon interaction in tight-binding approximation are used. The explicit expression for the gap parameter Δ0(k) is evaluated for the Einstein model of the solid. It is found that Δ0(k) consists of a constant part and an oscillatory part which varies as sin2kxa. The magnitude of oscillatory part is found to depend upon the cutoff energy ħωc, width of the singularity in the density of states near Fermi surface and overlap integral.

Domaines: Articles anciens

S. Prakash. Anisotropy of Gap Parameter in Cuprate Superconductors. Journal de Physique I, 1997, 7 (4), pp.611-620. ⟨10.1051/jp1:1997179⟩. ⟨jpa-00247348⟩