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arXiv · 1311.0631

Absence of broken time reversal symmetry beneath the surface of YBCO films

H. Saadaoui·Z. Salman·T. Prokscha·A. Suter·H. Huhtinen·P. Paturi·E. Morenzoni
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Abstract

We report the results of a search for spontaneous magnetism due to a time reversal symmetry breaking phase in the superconducting state of (110)-oriented YBCO films, expected near the surface in this geometry. Zero field and weak transverse field measurements performed using the low-energy muon spin rotation technique with muons implanted few nm inside optimally-doped YBCO-(110) films show no appearance of spontaneous magnetic fields below the superconducting temperature down to 2.9 K. Our results give an upper limit of ~0.02 mT for putative spontaneous internal fields.

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H. Saadaoui, Z. Salman, T. Prokscha, A. Suter, H. Huhtinen, P. Paturi, E. Morenzoni. 2013-11-04. Absence of broken time reversal symmetry beneath the surface of YBCO films. https://doi.org/10.1103/physrevb.88.180501

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