Engineering the speedup of quantum tunneling in Josephson systems via dissipation

Year: 2022

Authors: Maile D., Ankerhold J., Andergassen S., Belzig W., Rastelli G.

Autors Affiliation: Univ Ulm, Inst Komplexe Quantensyst, D-89069 Ulm, Germany; Univ Tubingen, Inst Theoret Phys, Morgenstelle 14, D-72076 Tubingen, Germany; Univ Tubingen, Ctr Quantum Sci, Morgenstelle 14, D-72076 Tubingen, Germany; Univ Konstanz, Fachbereich Phys, D-78457 Constance, Germany; Univ Trento, INO CNR BEC Ctr, I-38123 Povo, Italy; Univ Trento, Dipartimento Fis, I-38123 Povo, Italy

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.


Volume: 106 (4)      Pages from: 045408  to:

More Information: We are grateful to R. Dassonneville and J. Pekola for fruitful discussions. We acknowledge financial support from the MWK-RiSC grant (Research Seed Capital program Baden-Wurttemberg, Germany) . This research was also par- tially supported by the German Excellence Initiative by the Deutsche Forschungsgemeinschaft (DFG) through the SFBs 767 and 1432, as well as Project -ID 425217212.
KeyWords: superconducting Josephson circuits, quantum dissipation, engineered dissipation
DOI: 10.1103/PhysRevB.106.045408