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arXiv · 1512.05575

Characterizing unconventional superconductors from the spin structure of impurity-induced bound states

Vardan Kaladzhyan·Cristina Bena·Pascal Simon
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Abstract

Cooper pairs in two-dimensional unconventional superconductors with broken inversion symmetry are in a mixture of an even-parity spin-singlet pairing state with an odd-parity spin-triplet pairing state. We study the magnetic properties of the impurity bound states in such superconductors and find striking signatures in their spin polarization which allow to unambiguously discriminate a non-topological superconducting phase from a topological one. Moreover, we show how these properties, which could be measured using spin-polarized scanning tunneling microscopy (STM), also enable to determine the direction of the spin-triplet pairing vector of the host material and thus to distinguish between different types of unconventional pairing.

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Vardan Kaladzhyan, Cristina Bena, Pascal Simon. 2016-06-03. Characterizing unconventional superconductors from the spin structure of impurity-induced bound states. https://doi.org/10.1103/physrevb.93.214514

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