CIRCULARLY SYMMETRIC SOLITON SOLUTION IN AN ANNULAR JOSEPHSON JUNCTION
环形Josephson结中圆对称孤子解的微扰分析

We have analysed the circularly symmetric sine-Gordon equation with bias and dissipation by means of a simplified perturbation theory. Analytic solutions that describe the dynamical behaviour of a quasisoliton trapped within the annular junction have been obtained. Between the results of our theory and numerical simulation, there exists a good agreement for the first zero field step (ZFS) in the l-V characteristic. A brief discussion of our results is also presented.