Enhancement of the superconducting transition temperature due to multiband effect in the topological nodal-line semimetal Pb1−xSnxTaSe2
K. Kumarasinghe, A. Rahman, M. Tomlinson, D. Le, F. Joshua, L. Zhai, Y. Nakajima
DOI 10.1103/hsdq-2tp9 · Physical Review B
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
We report a systematic study of the normal-state and superconducting properties of single-crystal Pb1−xSnxTaSe2 (0≤x≤0.23). Sn doping enhances the superconducting temperature Tc up to 5.1 K while also significantly increasing impurity scattering in the crystals. For x=0 and 0.018, the specific-heat jump at Tc exceeds the Bardeen-Cooper-Schrieffer (BCS) weak-coupling value of 1.43, indicating the realization of strong-coupling superconductivity in undoped and slightly-Sn-doped PbTaSe2. Substituting Pb with more Sn lowers the specific-heat jump at Tc below the BCS value of 1.43, which cannot be explained by a single-gap model. Rather, the observed specific-heat data of moderately-Sn-doped PbTaSe2 (x=0.08 and 0.15) are reproduced by a two-gap model. Our density functional theory calculations suggest that three-dimensional Fermi pockets appear due to a reduction of the spin-orbit gap with Sn doping, and the multiband effect arising from these emergent Fermi pockets enhances the effective electron-phonon coupling strength, leading to the increase in Tc of Pb1−xSnxTaSe2.
Source-reported materials — not catalogue approval
| Formula | Reported Tc (K) | Pressure (GPa) | Type |
|---|---|---|---|
| Pb1-xSnxTaSe2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 5.1 | Pressure unresolved | midpoint |
| PbTaSe2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 4.02 | Pressure unresolved | midpoint |
| PbTaSe2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 3.58 | Pressure unresolved | unknown |
| SnTaSe2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 5.7 | Pressure not reported | unknown |
Similar papers
Superconducting properties in single crystals of the topological nodal semimetal PbTaSe2
similarity 0.95Cheng-Long Zhang et al.
Source status unknown — claims are unverified
Enhancement of the superconducting transition temperature due to multiband effect in the topological nodal-line semimetal PbSnTaSe
similarity 0.95K. Kumarasinghe et al. · 2024 · arXiv:2411.19932
Source status unknown — claims are unverified
Superconducting properties in a candidate topological nodal line semimetal SnTaS2 with a centrosymmetric crystal structure
similarity 0.95Dong-Yun Chen et al.
Source status unknown — claims are unverified
Topological phase transition under pressure in the topological nodal-line superconductor PbTaSe2
similarity 0.95C. Q. Xu et al.
Source status unknown — claims are unverified
Quantum oscillations in the noncentrosymmetric superconductor and topological nodal-line semimetal PbTaSe2
similarity 0.94Xitong Xu et al.
Source status unknown — claims are unverified
Nodeless superconducting gaps in noncentrosymmetric superconductor PbTaSe2 with topological bulk nodal lines
similarity 0.94M. X. Wang et al.
Source status unknown — claims are unverified