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Penetration Depth Measurements in MgB_2: Evidence for Unconventional Superconductivity

C. Panagopoulos·B. D. Rainford·T. Xiang·C. A. Scott·M. Kambara·I. H. Inoue
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Abstract

We have measured the magnetic penetration depth of the recently discovered binary superconductor MgB_2 using muon spin rotation and low field $ac$-susceptibility. From the damping of the muon precession signal we find the penetration depth at zero temperature is about 85nm. The low temperature penetration depth shows a quadratic temperature dependence, indicating the presence of nodes in the superconducting energy gap.

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C. Panagopoulos, B. D. Rainford, T. Xiang, C. A. Scott, M. Kambara, I. H. Inoue. 2001-03-02. Penetration Depth Measurements in MgB_2: Evidence for Unconventional Superconductivity. https://doi.org/10.1103/physrevb.64.094514

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