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Impurity Site NMR Relaxation in Unconventional Superconductors

Masashige Matsumoto
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Abstract

Impurity nuclear spin relaxation is studied theoretically. A single impurity generates a bound state localized around the impurity atom in unconventional superconductors. With increasing impurity potential, the relaxation rate $T_1^{-1}$ is reduced by the impurity potential. However, it has a peak at low temperatures due to the impurity bound state. The peak disappears at non-impurity sites. The impurity site NMR measurement detecting a local electronic structure just on the impurity atom is very useful for identifying the unconventional pairing states.

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Masashige Matsumoto. 2001-09-24. Impurity Site NMR Relaxation in Unconventional Superconductors. https://doi.org/10.1143/jpsj.70.2505

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