TY - JOUR
T1 - Search for superconducting phases with broken time-reversal symmetry in d-wave grain boundary junctions and interfaces
AU - Neils, W. K.
AU - Plourde, B. L.T.
AU - Van Harlingen, D. J.
N1 - Funding Information:
Asymmetric 45°-grain boundary junctions, in which the lobe of the bulk order parameter in one electrode is adjacent to the node of the other, are ideal for probing the symmetry of the order parameter. The d-wave symmetry of the cuprates is clearly seen in the complex variation of the critical current with field, which is due to interference Work supported by the Department of Energy Basic Energy Sciences grant DE-FG02-96ER-45439 and by the National Science Foundation Science and Technology Center for Superconductivity grant NSF-DMR91-20000.
PY - 2000
Y1 - 2000
N2 - We are carrying out experiments designed to test for the onset of subdominant superconductor phases induced by scattering from surfaces in d-wave superconductors. Phases with complex order parameters dx-y2 2+is or dx-y2 2. have been predicted to arise from the suppression of the d-wave order parameter by Andreev reflection from the anisotropic order parameter. We have measured the critical current modulation in grain boundary junctions fabricated from pure and magnetically-doped cuprate films, searching for signatures of a phase transition to a secondary order parameter state. We have also imaged the magnetic field distribution in fabricated superconductor thin films using Scanning SQUID Microscopy, searching for spontaneous circulating currents along the film edges arising from the onset of superconducting phases with broken time-reversal symmetry. Preliminary results show no evidence for complex secondary phases at (110)-surfaces in YBCO.
AB - We are carrying out experiments designed to test for the onset of subdominant superconductor phases induced by scattering from surfaces in d-wave superconductors. Phases with complex order parameters dx-y2 2+is or dx-y2 2. have been predicted to arise from the suppression of the d-wave order parameter by Andreev reflection from the anisotropic order parameter. We have measured the critical current modulation in grain boundary junctions fabricated from pure and magnetically-doped cuprate films, searching for signatures of a phase transition to a secondary order parameter state. We have also imaged the magnetic field distribution in fabricated superconductor thin films using Scanning SQUID Microscopy, searching for spontaneous circulating currents along the film edges arising from the onset of superconducting phases with broken time-reversal symmetry. Preliminary results show no evidence for complex secondary phases at (110)-surfaces in YBCO.
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U2 - 10.1016/S0921-4534(00)00946-1
DO - 10.1016/S0921-4534(00)00946-1
M3 - Article
AN - SCOPUS:0343832909
SN - 0921-4534
VL - 341-348
SP - 1705
EP - 1706
JO - Physica C: Superconductivity and its applications
JF - Physica C: Superconductivity and its applications
IS - PART 2
ER -