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

Baruch Horovitz^1,2 and Anatoly Golub¹

¹Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
²Ilze Katz Center for Nanotechnology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel

(Received 18 June 2003; published 10 December 2003)

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 wave vector q and finite frequency ; however, at finite q, 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. ©2003 The American Physical Society

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