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Superconductors with broken time-reversal symmetry: Spontaneous magnetization and quantum Hall effects

Baruch Horovitz·Anatoly Golub
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Abstract

Broken time reversal symmetry (BTRS) in d+id' as well as in d+is superconductors is studied and is shown to yield current carrying surface states. We evaluate the temperature and thickness dependence of the resulting spontaneous magnetization and show a marked difference between weak and strong BTRS. We also derive the Hall conductance which vanishes at zero wavevector q and finite frequency w, however at finite q,w it has an unusual structure. The chirality of the surface states leads to quantum Hall effects for spin and heat transport in d+id' superconductors.

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Baruch Horovitz, Anatoly Golub. 2003-06-28. Superconductors with broken time-reversal symmetry: Spontaneous magnetization and quantum Hall effects. https://doi.org/10.1103/physrevb.68.214503

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