Effect of dissipation on the decay-rate phase transition

TL;DR

This paper investigates how dissipation influences the nature and characteristics of decay-rate phase transitions in quantum tunneling models, revealing that dissipation can alter the transition order and affect decay rates.

Contribution

It derives a general condition for sharp decay-rate phase transitions in dissipative tunneling models with position-dependent mass, highlighting dissipation's impact on transition order.

Findings

Dissipation can change the order of phase transitions in quantum tunneling.

Ohmic dissipation enlarges the parameter range for first-order transitions.

Dissipation suppresses decay rates near the transition temperature in second-order transitions.

Abstract

A general condition for sharp transition of decay rate from quantum to thermal regimes is derived in dissipative tunneling models when position dependent mass is involved. It is shown that the effect of dissipation in general changes the order of the phase transition. Especially, for the models with constant mass the Ohmic dissipation enlarges the range of parameters for first-order phase transitions. In the case of second-order phase transition the Ohmic dissipation suppresses the decay rate near the transition temperature(T_c). For the super-Ohmic case the dissipation yields an opposite effects to the Ohmic dissipation within exponential approximation.