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 nonperturbative infinite-randomness critical point with unconventional activated dynamical scaling while super-Ohmic damping leads to conventional behavior. We discuss applications to the superconductor-metal transition in nanowires and to the Hertz theory of the itinerant antiferromagnetic transition.
J. A. Hoyos et al., "Effects of Dissipation on a Quantum Critical Point with Disorder," Physical Review Letters, American Physical Society (APS), Jan 2007.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevLett.99.230601
National Science Foundation (U.S.)
Keywords and Phrases
Energy dissipation; Phase transformations (Statistical physics)
Article - Journal
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