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arXiv · 1406.3022

Spectral function of a localized fermion coupled to the Wilson-Fisher conformal field theory

Andrea Allais·Subir Sachdev
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Abstract

We describe the dynamics of a single fermion in a dispersionless band coupled to the 2+1 dimensional conformal field theory (CFT) describing the quantum phase transition of a bosonic order parameter with N components. The fermionic spectral functions are expected to apply to the vicinity of quantum critical points in two-dimensional metals over an intermediate temperature regime where the Landau damping of the order parameter can be neglected. Some of our results are obtained by a mapping to an auxiliary problem of a CFT containing a defect line with an external field which locally breaks the global O(N) symmetry.

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Andrea Allais, Subir Sachdev. 2014-06-11. Spectral function of a localized fermion coupled to the Wilson-Fisher conformal field theory. https://doi.org/10.1103/physrevb.90.035131

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