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arXiv · 1906.02799

Strong Particle-Hole Symmetry Breaking in a 200 kelvin Superconductor

Soham S. Ghosh·Yundi Quan·Warren E. Pickett
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Abstract

The superconducting state of metals has long provided a classic example of particle-hole symmetry (PHS) at low energy. Fermionic self-energy results based on first principles theory for the electron-phonon coupling in H$_3$S presented here illustrate strong PHS-breaking dynamics arising from the underlying sharp structure in the fermionic density of states. Thus H$_3$S is not only the superconductor with the highest critical temperature $T_c$ (through 2018), but its low energy, low temperature properties deviate strongly from textbook behavior. The minor momentum and band dependence of the fermionic self-energy allows evaluation of the momentum-resolved and zone-averaged spectral densities and interacting thermal distribution function, all of which clearly illustrate strong particle-hole asymmetry.

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Soham S. Ghosh, Yundi Quan, Warren E. Pickett. 2019-06-06. Strong Particle-Hole Symmetry Breaking in a 200 kelvin Superconductor. https://doi.org/10.1103/physrevb.100.094521

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