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arXiv · 2004.06545

Magnetic impurities in thin films and 2D Ising superconductors

David Möckli·Menashe Haim·Maxim Khodas
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Abstract

In the theory of dilute magnetic impurities in superconductors, the effect of all impurity spin-components is expressed via a single magnetic scattering rate $\Gamma_\mathrm{m}$. In a more realistic setting, magnetic impurities are anisotropic. In this case, the spatial randomness of three spin-components of impurities gives rise to generally different scattering rates $\Gamma_i$ ($i=1,2,3$). We explore the effects of anisotropic magnetic impurities on the in-plane critical field in 2D superconductors. We discuss singlet, triplet and parity-mixed order parameters allowed in systems without the inversion center. Also, the addition of a small amount of magnetic impurities may cause singlet to triplet crossovers. In all cases, different components of impurity spin affect the magnetic field -- temperature phase diagram differently. We show that anisotropy of the magnetic impurities can serve as a probe of unconventional triplet or parity-mixed superconductivity.

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David Möckli, Menashe Haim, Maxim Khodas. 2020-04-14. Magnetic impurities in thin films and 2D Ising superconductors. https://doi.org/10.1063/5.0010773

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