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arXiv · 1805.09432

Spontaneous Edge Current in Higher Chirality Superconductors

Xin Wang·Zhiqiang Wang·Catherine Kallin
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Abstract

The effects of finite temperature, Meissner screening and surface roughness on the spontaneous edge current for higher chirality quasi-two dimensional superconductors are studied in the continuum limit using the quasiclassical Eilenberger equations. We find that the total spontaneous current is non-zero at finite temperature $T$ and maximized near $T=T_c/2$, where $T_c$ is the transition temperature, although it vanishes at $T=0$. In the presence of surface roughness, we observe a surface current inversion in the chiral $d$-wave case that can be understood in terms of a disorder induced $s$-wave pairing component in the rough surface regime. This conclusion is supported by a Ginzburg-Landau analysis. However, this current inversion is non-universal beyond the continuum limit as demonstrated by self-consistent lattice Bogoliubov-de Gennes calculations.

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Xin Wang, Zhiqiang Wang, Catherine Kallin. 2018-09-04. Spontaneous Edge Current in Higher Chirality Superconductors. https://doi.org/10.1103/physrevb.98.094501

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