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Nonperturbative renormalization-group approach for quantum dissipative systems

Ken-Ichi Aoki·Atsushi Horikoshi
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Abstract

We analyze the dissipative quantum tunneling in the Caldeira-Leggett model by the nonperturbative renormalization-group method. We classify the dissipation effects by introducing the notion of effective cutoffs. We calculate the localization susceptibility to evaluate the critical dissipation for the quantum-classical transition. Our results are consistent with previous semiclassical arguments, but give considerably larger critical dissipation.

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Ken-Ichi Aoki, Atsushi Horikoshi. 2003-06-03. Nonperturbative renormalization-group approach for quantum dissipative systems. https://doi.org/10.1103/physreva.66.042105

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