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arXiv · 0910.5557

Anisotropic order parameter in Li-intercalated layered superconductor Li$_x$ZrNCl

M. Hiraishi·R. Kadono·M. Miyazaki·S. Takeshita·Y. Taguchi·Y. Kasahara·T. Takano·T. Kishiume·Y. Iwasa
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Abstract

In this study, it is shown that in a layered nitride superconductor, i.e., LixZrNCl (0.07<=x<=0.21), the superconducting order parameter is highly anisotropic in a sample with x=0.12, as inferred from both the temperature and the magnetic field dependences of the muon depolarization rate (sigma_s, proportional to the superfluid density). Moreover, the tendency of strong anisotropy with an increase in x is indicated by the T dependence of sigma_s. These observations are in good agreement with the recent theory that predicts the development of anisotropy in a d+id' gap upon carrier filling to the bands with disconnected Fermi surfaces on a honeycomb lattice.

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M. Hiraishi, R. Kadono, M. Miyazaki, S. Takeshita, Y. Taguchi, Y. Kasahara, T. Takano, T. Kishiume, Y. Iwasa. 2010-01-21. Anisotropic order parameter in Li-intercalated layered superconductor Li$_x$ZrNCl. https://doi.org/10.1103/physrevb.81.014525

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