Effects of a resonant cavity on macroscopic quantum tunneling of fluxons in long Josephson junctions

Article

关键词: OSCILLATIONS;    DYNAMICS;    SYSTEMS;    QUBITS;    STATES;    PAIR;   

DOI  :  10.1103/PhysRevB.83.064503

来源: SCIE

【 摘 要 】

We investigate the effects of a high-quality resonant cavity on macroscopic quantum tunneling (MQT) of fluxons from both a metastable state to continuum and from one degenerate ground state of a double-well potential to the other. By using a set of two coupled perturbed sine-Gordon equations, we describe the tunneling processes in linear long Josephson junctions and find that MQT in the resonant cavity increases due to potential renormalization, induced by the interaction between the fluxon and the cavity. Enhancement of the MQT rate in the weak-coupling regime is estimated by using the experimentally accessible range of the model parameters. The tunneling rate from the metastable state is found to increase weakly with increasing junction-cavity interaction strength. However, the energy splitting between the two degenerate ground states of the double-well potential increases significantly with increasing both the interaction strength and the frequency of the resonant cavity mode. Finally, we discuss how the resonant cavity may be used to tune the property of Josephson vortex quantum bits.

【 授权许可】

Free