Stochastic resonance and nonlinear response in a dissipative quantum two-state system

TL;DR

This paper investigates how a dissipative quantum two-state system responds to an external ac field, revealing quantum stochastic resonance phenomena and analyzing the amplitude of coherent oscillations at high temperatures.

Contribution

It provides an analytical study of quantum stochastic resonance in a dissipative two-level system using quantum Langevin equations, extending previous numerical findings.

Findings

Quantum stochastic resonance observed in the system.

Amplitude of coherent oscillations analyzed at high temperature.

Qualitative agreement with earlier numerical results.

Abstract

We study the dynamics of a dissipative two-level, system driven by a monochromatic ac field, starting from the usual spin-boson Hamiltonian. The quantum Langevin equations for the spin variables are obtained. The amplitude of the coherent oscillations in the average position of the particle is studied in the high temperature limit. The system exhibits quantum stochastic resonance in qualitative agreement with earlier numerical results.