Multi-band description of the upper critical field of bulk FeSe

التفاصيل البيبلوغرافية
العنوان: Multi-band description of the upper critical field of bulk FeSe
المؤلفون: Bristow, M., Gower, A., Prentice, J. C. A., Watson, M. D., Zajicek, Z., Blundell, S. J., Haghighirad, A. A., McCollam, A., Coldea, A. I.
المصدر: Phys. Rev. B 108, 184507 (2023)
سنة النشر: 2023
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Superconductivity, Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons
الوصف: The upper critical field of multi-band superconductors can be an essential quantity to unravel the nature of superconducting pairing and its interplay with the electronic structure. Here we experimentally map out the complete upper critical field phase diagram of FeSe for different magnetic field orientations at temperatures down to 0.3 K using both resistivity and torque measurements. The temperature dependence of the upper critical field reflects that of a multi-band superconductor and requires a two-band description in the clean limit with band coupling parameters favouring interband over intraband interactions. Despite the relatively small Maki parameter in FeSe of $\alpha \sim 1.6$, the multi-band description of the upper critical field is consistent with the stabilization of a FFLO state below $T/T_{\rm c}\sim 0.3$. We find that the anomalous behaviour of the upper critical field is linked to a departure from the single-band picture, and FeSe provides a clear example where multi-band effects and the strong anisotropy of the superconducting gap need to be taken into account.
Comment: 15 pages, 10 figures (manuscript and the supplemental materials
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.108.184507
URL الوصول: http://arxiv.org/abs/2311.04188
رقم الأكسشن: edsarx.2311.04188
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevB.108.184507