Symmetry Protected Topological Metals

Xuzhe Ying; Alex Kamenev

doi:10.1103/physrevlett.121.086810

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arXiv · 1804.02456

Symmetry Protected Topological Metals

Xuzhe Ying·Alex Kamenev

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Abstract

We show that sharply defined topological quantum phase transitions are not limited to states of matter with gapped electronic spectra. Such transitions may also occur between two gapless metallic states both with extended Fermi surfaces. The transition is characterized by a discontinuous, but not quantized, jump in an off-diagonal transport coefficient. Its sharpness is protected by a symmetry, such as e.g. particle-hole, which remains unbroken across the transition. We present a simple model of this phenomenon, based on 2D $p+ip$ superconductor with an applied supercurrent, and discuss its geometrical interpretation.

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Xuzhe Ying, Alex Kamenev. 2018-04-06. Symmetry Protected Topological Metals. https://doi.org/10.1103/physrevlett.121.086810

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