Effective model for a short Josephson junction with a phase discontinuity

Article

关键词: FERROMAGNET;    FIELD;    FLUX;   

DOI  :  10.1103/PhysRevB.93.134514

来源: SCIE

【 摘 要 】

We consider a short Josephson junction with a phase discontinuity kappa created, e.g., by a pair of tiny current injectors, at some point x(0) along the width of the junction. We derive the effective current-phase relation (CPR) for the system as a whole, i.e., reduce it to an effective pointlike junction. From the effective CPR we obtain the ground state of the system and predict the dependence of its critical current on.. We show that in a large range of kappa values the effective junction behaves as a phi(0) Josephson junction, i.e., has a unique ground state phase phi(0) within each 2 pi interval. For kappa approximate to pi and x(0) near the middle of the junction one obtains a phi(0) +/- phi junction, i.e., a Josephson junction with degenerate ground state phase phi(0) +/- phi within each 2 pi interval. Further, in view of possible escape experiments especially in the quantum domain, we investigate the scaling of the energy barrier and eigenfrequency close to the critical currents and predict the behavior of the escape histogram width sigma(kappa) in the regime of the macroscopic quantum tunneling.

【 授权许可】

Free