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arXiv · 0705.1865

Effects of dissipation on a quantum critical point with disorder

J. A. Hoyos·Chetan Kotabage·Thomas Vojta
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Abstract

We study the effects of dissipation on a disordered quantum phase transition with O$(N)$ order parameter symmetry by applying a strong-disorder renormalization group to the Landau-Ginzburg-Wilson field theory of the problem. We find that Ohmic dissipation results in a non-perturbative infinite-randomness critical point with unconventional activated dynamical scaling while superohmic damping leads to conventional behavior. We discuss applications to the superconductor-metal transition in nanowires and to Hertz' theory of the itinerant antiferromagnetic transition.

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J. A. Hoyos, Chetan Kotabage, Thomas Vojta. 2007-12-04. Effects of dissipation on a quantum critical point with disorder. https://doi.org/10.1103/physrevlett.99.230601

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