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arXiv · 0804.1359

Doped Kagome System as Exotic Superconductor

Wing-Ho Ko·Patrick A. Lee·Xiao-Gang Wen
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Abstract

A Chern--Simons theory for the doped spin-1/2 kagomé system is constructed, from which it is shown that the system is an exotic superconductor that breaks time-reversal symmetry. It is also shown that the system carries minimal vortices of flux $hc/4e$ (as opposed to the usual $hc/2e$ in conventional superconductors) and contains fractional quasiparticles (including fermionic quasiparticles with \emph{semionic} mutual statistics and spin-1/2 quasiparticles with \emph{bosonic} self-statistics) in addition to the usual spin-1/2 fermionic Bougoliubov quasiparticle. Two Chern--Simons theories--one with an auxiliary gauge field kept and one with the auxiliary field and a redundant matter field directly eliminated--are presented and shown to be consistent with each other.

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Wing-Ho Ko, Patrick A. Lee, Xiao-Gang Wen. 2009-04-15. Doped Kagome System as Exotic Superconductor. https://doi.org/10.1103/physrevb.79.214502

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