تقرير
Electron-phonon coupling and spin fluctuations in the Ising superconductor NbSe$_{2}$
| العنوان: | Electron-phonon coupling and spin fluctuations in the Ising superconductor NbSe$_{2}$ |
|---|---|
| المؤلفون: | Das, S., Paudyal, H., Margine, E. R., Agterberg, D. F., Mazin, I. I. |
| سنة النشر: | 2022 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Superconductivity, Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons |
| الوصف: | Ising superconductivity, observed experimentally in NbSe$_{2}$ and similar materials, has generated tremendous interest. Recently, attention was called to the possible role that spin fluctuations (SF) play in this phenomenon, in addition to the dominant electron-phonon coupling (EPC); the possibility of a predominantly-triplet state was discussed and led to a conjecture of viable singlet-triplet Leggett oscillations. However, these hypotheses have not been put to a quantitative test. In this paper, we report first principle calculations of the EPC and also estimate coupling with SF, including full momentum dependence. We find that: (1) EPC is strongly anisotropic, largely coming from the K-K' scattering, and therefore excludes triplet symmetry even as an excited state; (2) superconductivity is substantially weakened by SF, but anisotropy remains as above; and, (3) we do find the possibility of a Leggett mode, not in a singlet-triplet but in an $s_{++}$ - $s_\pm$ channel. Comment: 11 pages, 4 figures |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2210.00745 |
| رقم الأكسشن: | edsarx.2210.00745 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |