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Two phase transitions in (s+id)-wave Bardeen-Cooper-Schrieffer superconductivity

Angsula Ghosh·Sadhan K. Adhikari
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Abstract

We establish universal behavior in temperature dependencies of some observables in $(s+id)$-wave BCS superconductivity in the presence of a weak $s$ wave. There also could appear a second second-order phase transition. As temperature is lowered past the usual critical temperature $T_c$, a less ordered superconducting phase is created in $d$ wave, which changes to a more ordered phase in $(s+id)$ wave at $T_{c1}$ ($< T_c$). The presence of two phase transitions manifest in two jumps in specific heat at $T_c$ and $T_{c1}$. The temperature dependencies of susceptibility, penetration depth, and thermal conductivity also confirm the new phase transition.

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Angsula Ghosh, Sadhan K. Adhikari. 1998-05-19. Two phase transitions in (s+id)-wave Bardeen-Cooper-Schrieffer superconductivity. https://doi.org/10.1088/0953-8984%2F10%2F20%2F002

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