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arXiv · 1209.4644

Quantum criticality of reconstructing Fermi surfaces in antiferromagnetic metals

Junhyun Lee·Philipp Strack·Subir Sachdev
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Abstract

We present a functional renormalization group analysis of a quantum critical point in two-dimensional metals involving Fermi surface reconstruction due to the onset of spin-density wave order. Its critical theory is controlled by a fixed point in which the order parameter and fermionic quasiparticles are strongly coupled and acquire spectral functions with a common dynamic critical exponent. We obtain results for critical exponents and for the variation in the quasiparticle spectral weight around the Fermi surface. Our analysis is implemented on a two-band variant of the spin-fermion model which will allow comparison with sign-problem-free quantum Monte Carlo simulations.

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Junhyun Lee, Philipp Strack, Subir Sachdev. 2013-01-09. Quantum criticality of reconstructing Fermi surfaces in antiferromagnetic metals. https://doi.org/10.1103/physrevb.87.045104

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