Engineering the speedup of quantum tunneling in Josephson systems via dissipation

TL;DR

This paper theoretically explores how tailored dissipation can enhance quantum tunneling escape rates in Josephson systems, with potential implications for quantum device control and design.

Contribution

It demonstrates that charge dissipation can increase quantum escape rates in Josephson junctions, even in low Ohmic regimes, providing new insights into dissipation effects.

Findings

Charge dissipation enhances quantum escape rate.

Enhancement occurs in low Ohmic dissipation regimes.

Experimental parameter spaces for observing the effect are identified.

Abstract

We theoretically investigate the escape rate occurring via quantum tunneling in a system affected by tailored dissipation. Specifically, we study the environmental assisted quantum tunneling of the superconducting phase in a current-biased Josephson junction. We consider Ohmic resistors inducing dissipation both in the phase and in the charge of the quantum circuit. We find that the charge dissipation leads to an enhancement of the quantum escape rate. This effect appears already in the low Ohmic regime and also occurs in the presence of phase dissipation that favors localization. Inserting realistic circuit parameters, we address the question of its experimental observability and discuss suitable parameter spaces for the observation of the enhanced rate.