Stability of nodal quasi-particles in superconductors with coexisting orders

E. Berg; C-C. Chen; S. A. Kivelson

doi:10.1103/physrevlett.100.027003

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arXiv · 0710.0113

Stability of nodal quasi-particles in superconductors with coexisting orders

E. Berg·C-C. Chen·S. A. Kivelson

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Abstract

We establish a condition for the perturbative stability of zero energy nodal points in the quasi-particle spectrum of superconductors in the presence of coexisting \textit{commensurate} orders. The nodes are found to be stable if the Hamiltonian is invariant under time reversal followed by a lattice translation. The principle is demonstrated with a few examples. Some experimental implications of various types of assumed order are discussed in the context of the cuprate superconductors.

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E. Berg, C-C. Chen, S. A. Kivelson. 2008-01-29. Stability of nodal quasi-particles in superconductors with coexisting orders. https://doi.org/10.1103/physrevlett.100.027003

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