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arXiv · 0802.1868

Renormalization group for phases with broken discrete symmetry near quantum critical points

P. Jakubczyk·P. Strack·A. A. Katanin·W. Metzner
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Abstract

We extend the Hertz-Millis theory of quantum phase transitions in itinerant electron systems to phases with broken discrete symmetry. Using a set of coupled flow equations derived within the functional renormalization group framework, we compute the second order phase transition line T_c(delta), with delta a non-thermal control parameter, near a quantum critical point. We analyze the interplay and relative importance of quantum and classical fluctuations at different energy scales, and we compare the Ginzburg temperature T_G to the transition temperature T_c, the latter being associated with a non-Gaussian fixed-point.

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P. Jakubczyk, P. Strack, A. A. Katanin, W. Metzner. 2008-05-23. Renormalization group for phases with broken discrete symmetry near quantum critical points. https://doi.org/10.1103/physrevb.77.195120

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