2014/05/27 by Denis Feinberg, D. Feinberg, C. A. Balseiro +1
Physics and Astronomy · #Condensed matter physics #Degenerate energy levels #Frustration #Inductance #Josephson effect #Magnetic field #Magnetic flux #Magnetic moment #Phase (matter) #Physics #Physics of Superconductivity and Magnetism #Pi Josephson junction #Quantum and electron transport phenomena #Quantum dot #Quantum mechanics #Spin (aerodynamics) #Superconductivity #Topological Materials and Phenomena #Voltage #Vortex #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.90.075432
published as Phys. Rev. B 90, 075432 (2014)
arxiv created 2014/05/27 · openalex publication_date 2014/08/26 · arxiv updated 2015/06/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
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 \ensuremathπ-shift of the phase, the bijunction forming a triangular unit is frustrated. This frustration is studied within both 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 one to create a tunable ``\ensuremathφ''-junction whose equilibrium phase can take any value. For large enough inductance, it generates noninteger spontaneous flux. Multiloop configurations are also studied.