Kinetic theory of a quantum particle interacting with a dissipative environment

Dana A. Browne, Cornell University Laboratory of Atomic and Solid State Physics
Kenneth S. Chow, Cornell University Laboratory of Atomic and Solid State Physics
Vinay Ambegaokar, Cornell University Laboratory of Atomic and Solid State Physics

Abstract

We develop a kinetic theory for the real-time response of a quantum particle interacting with a macroscopic reservoir. We calculate in the low-damping limit the width and bath-induced frequency shift of the metastable tunneling levels of a resistively shunted Josephson junction and the enhancement of the tunneling rate upon the application of a weak microwave field. The results agree with experiment without adjustable parameters. At low temperatures the equation of motion for the phase of the junction can be written as that of a spin-(1/2) object in a time-dependent magnetic field. © 1987 The American Physical Society.