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arXiv · 0910.0696

Wavefunction topology of two-dimensional time-reversal symmetric superconductors

S. -K. Yip
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Abstract

We discuss the topology of the wavefunctions of two-dimensional time-reversal symmetric superconductors. We consider (a) the planar state, (b) a system with broken up-down reflection symmetry, and (c) a system with general spin-orbit interaction. We show explicitly how the relative sign of the order parameter on the two Fermi surfaces affects this topology, and clarify the meaning of the $Z_2$ classification for these topological states.

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S. -K. Yip. 2009-12-08. Wavefunction topology of two-dimensional time-reversal symmetric superconductors. https://doi.org/10.1007/s10909-010-0168-5

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