The Emergence of Anisotropic Superconductivity in the Nodal-line Semi-metal TlTaSe2

Mukhtar Lawan Adam; Ibrahim Buba Garba; Sulaiman Muhammad Gana; Bala Ismail Adamu; Abba Alhaji Bala; Abdulsalam Aji Suleiman; Ahmad Hamisu; Tijjani Hassan Darma; Auwal Musa; Abdulkadir S. Gidado

arXiv · 2310.13986

The Emergence of Anisotropic Superconductivity in the Nodal-line Semi-metal TlTaSe2

Mukhtar Lawan Adam·Ibrahim Buba Garba·Sulaiman Muhammad Gana·Bala Ismail Adamu·Abba Alhaji Bala·Abdulsalam Aji Suleiman·Ahmad Hamisu·Tijjani Hassan Darma·Auwal Musa·Abdulkadir S. Gidado

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Abstract

TlTaSe2 is a non-centrosymmetric quasi-2D crystal semi-metal hosting nodal-line topological features protected by mirror-reflection symmetry. Here, we investigated the superconducting properties of TlTaSe2 using the first-principles anisotropic Migdal-Eliashberg theory. The Fermi surface hosts well gapped multiband features contributed by the Ta 5d and Tl 6p orbitals. Moreso, anisotropic superconducting gaps were found to exist at 2.15 and 4.5 meV around the in-plane orbitals, coupling effectively with the in-plane phonons of the Ta and Tl atoms. Using the Allen-Dynes-modified McMillan formula, we found a superconducting transition temperature of 6.67 K, accompanied by a robust electron-phonon coupling constant {\lambda} of 0.970. This investigation provides valuable insights into the mechanisms underlying anisotropic superconductivity in TlTaSe2.

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Mukhtar Lawan Adam, Ibrahim Buba Garba, Sulaiman Muhammad Gana, Bala Ismail Adamu, Abba Alhaji Bala, Abdulsalam Aji Suleiman, Ahmad Hamisu, Tijjani Hassan Darma, Auwal Musa, Abdulkadir S. Gidado. 2023-10-21. The Emergence of Anisotropic Superconductivity in the Nodal-line Semi-metal TlTaSe2. https://arxiv.org/abs/2310.13986

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