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arXiv · 1606.00918

Finite temperature scaling close to Ising-nematic quantum critical points in two-dimensional metals

Matthias Punk
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Abstract

We study finite temperature properties of metals close to an Ising-nematic quantum critical point in two spatial dimensions. In particular we show that at any finite temperature there is a regime where order parameter fluctuations are characterized by a dynamical critical exponent $z=2$, in contrast to $z=3$ found at zero temperature. Our results are based on a simple Eliashberg-type approach, which gives rise to a boson self-energy proportional to $\Omega/\gamma(T)$ at small momenta, where $\gamma(T)$ is the temperature dependent fermion scattering rate. These findings might shed some light on recent Monte-Carlo simulations at finite temperature, where results consistent with $z=2$ were found.

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Matthias Punk. 2016-06-02. Finite temperature scaling close to Ising-nematic quantum critical points in two-dimensional metals. https://doi.org/10.1103/physrevb.94.195113

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