تقرير
Time-reversal invariant and fully gapped unconventional superconducting state in the bulk of the topological Nb0.25Bi2Se3
| العنوان: | Time-reversal invariant and fully gapped unconventional superconducting state in the bulk of the topological Nb0.25Bi2Se3 |
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| المؤلفون: | Das, Debarchan, Kobayashi, K., Smylie, M. P., Mielke III, C., Takahashi, T., Willa, K., Yin, J. -X., Welp, U., Hasan, M. Z., Amato, A., Luetkens, H., Guguchia, Z. |
| المصدر: | Phys. Rev. B 102, 134514 (2020) |
| سنة النشر: | 2020 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Superconductivity, Condensed Matter - Materials Science |
| الوصف: | Recently, the niobium (Nb)-doped topological insulator Bi_2Se_3, in which the finite magnetic moments of the Nb atoms are intercalated in the van der Waals gap between the Bi_2Se_3 layers, has been shown to exhibit both superconductivity with T_c = 3 K and topological surface states. Here we report on muon spin rotation experiments probing the temperature-dependent of effective magnetic penetration depth Lambda_eff(T) in the layered topological superconductor candidate Nb_0.25Bi_2Se_3. The exponential temperature dependence of lambda_(eff)^(-2)(T) at low temperatures suggests a fully gapped superconducting state in the bulk with the superconducting transition temperature T_c = 2.9 K and the gap to T_c ratio 2Delta/k_BT_c = 3.95(19). We also revealed that the ratio T_c/lambda_(eff)^(-2) is comparable to those of unconventional superconductors, which hints at an unconventional pairing mechanism. Furthermore, time reversal symmetry breaking was excluded in the superconducting state with sensitive zero-field muSR experiments. We hope the present results will stimulate theoretical investigations to obtain a microscopic understanding of the relation between superconductivity and the topologically non-trivial electronic structure of Nb_0.25Bi_2Se_3. Comment: 9 pages, 5 figures |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1103/PhysRevB.102.134514 |
| URL الوصول: | http://arxiv.org/abs/2005.11436 |
| رقم الأكسشن: | edsarx.2005.11436 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1103/PhysRevB.102.134514 |
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