Spontaneous Flux and Magnetic Interference Patterns in 0-π Josephson Junctions
نویسنده
چکیده
The spontaneous flux generation and magnetic field modulation of the critical current in a 0−π Josephson junction are calculated for different ratios of the junction length L to the Josephsen penetration depth λJ , and different ratios of the 0-junction length to the π-junction length. These calculations apply to a Pb-YBCO c-axis oriented junction with one YBCO twin boundary, as well as other experimental systems. Measurements of such a junction can provide information on the nature of the c-axis Josephson coupling and the symmetry of the order parameter in YBCO. We find spontaneous flux even for very short symmetric 0−π junctions, but asymmetric junctions have qualitatively different behavior. 73.40.Gk,73.40.Rw,74.50.+r,74.72.-h Typeset using REVTEX 1
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