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arXiv · 1007.4898

Evidence for time-reversal symmetry breaking in superconducting PrPt4Ge12

A. Maisuradze·W. Schnelle·R. Khasanov·R. Gumeniuk·M. Nicklas·H. Rosner·A. Leithe-Jasper·Yu. Grin·A. Amato·P. Thalmeier
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Abstract

Zero and longitudinal field muon spin rotation (muSR) experiments were performed on the superconductors PrPt4Ge12 and LaPt4Ge12. In PrPt4Ge12 below Tc a spontaneous magnetization with a temperature variation resembling that of the superfluid density appears. This observation implies time-reversal symmetry (TRS) breaking in PrPt4Ge12 below Tc = 7.9 K. This remarkably high Tc for an anomalous superconductor and the weak and gradual change of Tc and of the related specific heat anomaly upon La substitution in La_(1-x)Pr_xPt_4Ge_(12) suggests that the TRS breaking is due to orbital degrees of freedom of the Cooper pairs.

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A. Maisuradze, W. Schnelle, R. Khasanov, R. Gumeniuk, M. Nicklas, H. Rosner, A. Leithe-Jasper, Yu. Grin, A. Amato, P. Thalmeier. 2010-07-28. Evidence for time-reversal symmetry breaking in superconducting PrPt4Ge12. https://doi.org/10.1103/physrevb.82.024524

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