局域自旋超导双结中的自发涡旋态和$φ$结
Spontaneous vortex state and $φ$-junction in a superconducting bijunction with a localized spin
摘要：
在量子点带有磁矩的情况下，研究了由三个超导体通过量子点连接而成的约瑟夫森双结。在这样的点的参数范围内，如果插入到两端约瑟夫森结中，则产生相位的$π$ -移位，形成三角形单元的双结被破坏。这种挫折是在现象学和微观模型研究。阻挫稳定了以点为中心的相位涡旋，其中两个简并状态携带相反的涡旋，与磁矩的方向无关。在超导回路中嵌入双结允许产生可调谐的“$φ$“结，其平衡相位可以取任何值。当电感足够大时，它产生非整数的自发磁通。多回路配置也进行了研究。
英文摘要：
A Josephson bijunction made of three superconductors connected by a quantum dot is considered in the regime where the dot carries a magnetic moment. In the range of parameters where such a dot, if inserted in a two-terminal Josephson junction, creates a $π$-shift of the phase, the bijunction forming a triangular unit is frustrated. This frustration is studied both within a phenomenological and a microscopic model. Frustration stabilizes a phase vortex centered on the dot, with two degenerate states carrying opposite vorticities, independently of the direction of the magnetic moment. Embedding the bijunction in a superconducting loop allows to create a tunable "$φ$"-junction whose equilibrium phase can take any value. For large enough inductance, it generates noninteger spontaneous flux. Multi-loop configurations are also studied.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
