几何尺寸对圆对称环域Josephson结的准通量子激发的影响

THE GEOMETRY SIZE EFFECTS OF THE QUASI-FLUXON OF EXCITATION IN THE CIRCULAR SYMMETRIC ANNULAR JOSEPHSON JUNCTION

本文研究几何尺寸对圆对称环域Josephson结的扰动SGE 的环形准孤子波解的影响.数值计算结果表明,当圆对称环域结的内半径, γο=7.5λ时,已出现对应于环域结准通量子激发的环形准孤子波解,同时在I-V特性曲线上出现第一零场台阶.零场台阶的范围剧烈地依赖于环域结的内半径r。和结宽度( αγο-γο);然而几何尺寸对环形准孤子波解特性的影响则比较复杂.

In this paper, the geometry size effects of the ringshape quasi-soliton solutions in the perturbed Sine-Gordon equations (SGE) in the circular symmetric annular Josephson junction are investigated with numerical method. The perturbed SGE, when the inner radius r9 of the circular symmetric annular junctions is larger then or equal to 7.5λJ, there exists a kind of ring-shape quasi-soliton solutions, which correspond to the quasi-fluxon of excitation in the circular symmetric annular Josephson junction, and the first zero-field step also. The range of the first zero-field step depend strongly on the size of the inner radius γ0 and widths (αγ0-γ0) of the circular symmetric annular junctions, but the geometry size effects of the nature of the ring-shape quasi-solitons are more complicated.