Spontaneous macroscopic magnetization at the superconducting transition temperature of YBa 2 Cu 3 O 7-δ
作者： R. Carmi , E. Polturak , G. Koren , A. Auerbach
DOI: 10.1038/35009062
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摘要: A noteworthy feature of the high-temperature superconductors is unconventional symmetry superconducting order parameter. Several experiments1,2,3 have established that parameter has a four-fold under rotation lattice (the conventional is, in contrast, isotropic). An intriguing and much debated possibility that, certain cases, an additional imaginary component might be present, having isotropic s-wave4,5,6 or dxy symmetry7,8,9,10. consequence complex form + idxy it would break both reflection (parity, P) time-reversal (T) symmetry, clear signature which spontaneous appearance macroscopic magnetization at transition temperature. Broken T been reported5,11, but searches for effects combined P breaking so far yielded null results12,13,14,15. Here we report observation weak (∼10-5 gauss) magnetic field appears spontaneously temperature epitaxial thin films YBa2Cu3O7-δ. The signal originates near edges samples. One interpretation this carries intrinsic angular momentum, related to symmetries, other possibilities cannot yet excluded.
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