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arXiv · 0711.2494

Polar Kerr Effect Measurements of YBa2Cu3O6+x: Evidence for Broken Symmetry Near the Pseudogap Temperature

Jing Xia·Elizabeth Schemm·G. Deutscher·S. A. Kivelson·D. A. Bonn·W. N. Hardy·R. Liang·W. Siemons·G. Koster·M. M. Fejer·A. Kapitulnik
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Abstract

Polar Kerr effect in the high-Tc superconductor \YBCO was measured at zero magnetic field with high precision using a cyogenic Sagnac fiber interferometer. We observed non-zero Kerr rotations of order $\sim 1 μ$rad appearing near the pseudogap temperature $T^*$, and marking what appears to be a true phase transition. Anomalous magnetic behavior in magnetic-field training of the effect suggests that time reversal symmetry is already broken above room temperature.

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Jing Xia, Elizabeth Schemm, G. Deutscher, S. A. Kivelson, D. A. Bonn, W. N. Hardy, R. Liang, W. Siemons, G. Koster, M. M. Fejer, A. Kapitulnik. 2008-03-31. Polar Kerr Effect Measurements of YBa2Cu3O6+x: Evidence for Broken Symmetry Near the Pseudogap Temperature. https://doi.org/10.1103/physrevlett.100.127002

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