Weak anti-localization and spin-momentum locking in topological insulator Ta$_2$Ni$_3$Te$_5$

TL;DR

This study investigates the electronic, magnetic, and transport properties of the layered topological insulator Ta$_2$Ni$_3$Te$_5$, revealing weak anti-localization and spin-momentum locking indicative of potential quantum spin Hall applications.

Contribution

The paper provides the first detailed analysis of WAL and spin-momentum locking in Ta$_2$Ni$_3$Te$_5$, highlighting its suitability for quantum spin Hall devices.

Findings

Observation of weak anti-localization effect in magnetotransport data

Detection of spin-momentum locking via Berry paramagnetism

Large magnetoresistance indicating strong spin-orbit coupling

Abstract

We report the synthesis, structural characterization, and investigation of electrical transport, magnetic and specific heat properties of bulk semiconducting layered material Ta$_2$Ni$_3$Te$_5$. Ta$_2$Ni$_3$Te$_5$ crystallizes in the centrosymmetric orthorhombic structure with space group Pnma. Temperature-dependent resistivity shows a transition from semiconducting to metallic nature below 7 K. Low-temperature magnetotransport studies show large magnetoresistance with the signature of weak anti-localization (WAL) effect. The magnetoconductivity data has been used to explore the origin of the WAL effect, extract relevant parameters, and study their variation with temperature. The presence of significant electron-phonon interaction is evident from the MR vs. B/R plot (Kohler's plot). Isothermal field-dependent magnetization studies show Berry paramagnetism as the signature for spin-orbit coupling-induced spin-momentum locking. Observation of WAL effect and spin-momentum locking phenomenon demonstrate Ta$_2$Ni$_3$Te$_5$ as a promising low dimensional material for quantum spin Hall insulator-based applications.