Superconductivity and Fermi Surface Anisotropy in Transition Metal Dichalcogenide NbTe ₂

Abstract

Transition metal dichalcogenides, featuring layered structures, have aroused enormous interest as a platform for novel physical phenomena and a wide range of potential applications. Among them, special interest has been placed upon WTe2 and MoTe2, which exhibit non-trivial topology both in single layer and bulk as well as pressure induced or enhanced superconductivity. We study another distorted 1T material NbTe2 through systematic electrical transport measurements. Intrinsic superconductivity with onset transition temperature (𝑇 onset c ) up to 0.72 K is detected where the upper critical field (𝐻c) shows unconventional quasi-linear behavior, indicating spin-orbit coupling induced p-wave paring. Furthermore, a general model is proposed to fit the angledependent magnetoresistance, which reveals the Fermi surface anisotropy of NbTe2. Finally, non-saturating linear magnetoresistance up to 50 T is observed and attributed to the quantum limit transport.

Eightfold fermionic excitation in a charge density wave compound

“…Often used for SdH oscillation analysis is a simplified version of the standard Lifshitz-Kosevich (LK) formula [45,47]: Angular-dependent magnetoresistance [48] or magnetic oscillation is a powerful tool to study FS anisotropy. An offset plot of FFT of oscillations at different θ (SM [31] Fig.…”

“…Angular-dependent magnetoresistance [48] or magnetic oscillation is a powerful tool to study FS anisotropy. Offset plot of FFT of oscillations at different 𝜃 (SM [31] Fig.…”

Evolution of Structural and Electronic Properties in NbTe2 under High Pressure

“…Zhang et al reported the collapse of superconductivity when applied a pressure of 1.3 GPa on NbTe 2 . 21 Vaidya et al measured the electrical resistivity under pressure and found no abnormal change. 23 In addition, little is known about the properties of isostructural 1T″-TaTe 2 under pressure.…”

Optical spectroscopy and ultrafast pump-probe study of structural phase transition in 1T'-TaTe2

“…Additionally, applying external pressure could achieved the bulk superconductivity of TaTe 2 between 4-6 K in the pressure range of 21-50 GPa 22 . As for isostructural CDW compound 1T'-NbTe 2 with 3×1 superstructure at 300 K 23 , such a LT phase has not been observed but exhibits superconductivity at T c ∼ 0.5 K 24 . Another analogue layered compound IrTe 2 with a 5d heavy transition metal element and strong Te-Te interlayer interaction shows a structural phase transition and transport properties anomaly as well 25 .…”