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arXiv · 1305.0063

Coexistence of the superconducting energy gap and pseudogap above and below the transition temperature of superconducting cuprates

Jeffery L. Tallon·Felix Barber·James G. Storey·John W. Loram
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Abstract

We express the superconducting gap, $\Delta(T)$, in terms of thermodynamic functions in both $s$- and d-wave symmetries. Applying to Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ and Y$_{0.8}$Ca$_{0.2}$Ba$_2$Cu$_3$O$_{7-\delta}$ we find that for all dopings $\Delta(T)$ persists, as a partial gap, high above $T_c$ due to strong superconducting fluctuations. Therefore in general two gaps are present above $T_c$, the superconducting gap and the pseudogap, effectively reconciling two highly polarized views concerning pseudogap physics.

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Jeffery L. Tallon, Felix Barber, James G. Storey, John W. Loram. 2013-05-01. Coexistence of the superconducting energy gap and pseudogap above and below the transition temperature of superconducting cuprates. https://doi.org/10.1103/physrevb.87.140508

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