Effects of dissipation on a quantum critical point with disorder.
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.
Hoyos
José A
JA
Department of Physics, University of Missouri-Rolla, Rolla, Missouri 65409, USA.
Kotabage
Chetan
C
Vojta
Thomas
T