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Chiral symmetry breaking and violation of the Wiedemann-Franz law in underdoped cuprates

Guo-Zhu Liu·Geng Cheng
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Abstract

We propose that the recently observed violation of the Wiedemann-Franz law in the normal state of underdoped cuprates is caused by spin-charge separation and dynamical chiral symmetry breaking in a (2+1)-dimensional system consisting of massless Dirac fermions, charged bosons and a gauge field. While the d-wave spinon gap vanishes at the Fermi points, the nodal fermions acquire a finite mass due to strong gauge fluctuations. This mass provides a gap below which no free fermions can be excited. This implies that there is not a residual linear term for the thermal conductivity, in good agreement with experiments. Other physical implications of the CSB are also discussed.

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Guo-Zhu Liu, Geng Cheng. 2002-08-03. Chiral symmetry breaking and violation of the Wiedemann-Franz law in underdoped cuprates. https://doi.org/10.1103/physrevb.66.100505

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