Interplay of magnetic field and magnetic impurities in Ising superconductors

التفاصيل البيبلوغرافية
العنوان: Interplay of magnetic field and magnetic impurities in Ising superconductors
المؤلفون: Fang, Wuzhang, Haim, M., Belashchenko, K. D., Khodas, M., Mazin, I. I.
المصدر: Phys. Rev. B 109, 174509 (2024)
سنة النشر: 2023
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Superconductivity, Condensed Matter - Materials Science
الوصف: Phonon-driven $s$-wave superconductivity is fundamentally antagonistic to uniform magnetism, and field-induced suppression of the critical temperature is one of its canonical signatures. Examples of the opposite are unique and require fortuitous cancellations and very fine parameter tuning. The recently discovered Ising superconductors violate this rule: an external magnetic field applied in a certain direction does not suppress superconductivity in an ideal, impurity-free material. We propose a simple and experimentally accessible system where the effects of spin-conserving and spin-flip scattering can be studied in a controlled way, namely NbSe$_2$ monolayers dosed with magnetic $3d$ atoms. We predict that the critical temperature is slightly increased by an in-plane magnetic field in NbSe$_2$ dosed with Cr. Due to the band spin splitting, magnetic spin-flip scattering requires a finite momentum transfer, while spin-conserving scattering does not. If the magnetic anisotropy is easy-axis, an in-plane field reorients the impurity spins and transforms spin-conserving scattering into spin-flip. The critical temperature is enhanced if the induced magnetization of NbSe$_2$ has a substantial long-range component, as is the case for Cr ions.
Comment: 13 pages, 8 figures
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.109.174509
URL الوصول: http://arxiv.org/abs/2306.01700
رقم الأكسشن: edsarx.2306.01700
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevB.109.174509