Observation of Weak Anti-localization in thin films of the Topological Semimetal Candidate PdSb$_{2}$

TL;DR

This study investigates weak anti-localization and electron-electron interactions in thin films of the topological semi-metal candidate PdSb$_{2}$, revealing insights into transport channels and phase relaxation mechanisms.

Contribution

First detailed analysis of WAL and EEI effects in PdSb$_{2}$ thin films, linking transport channels with topological surface and bulk states.

Findings

WAL observed indicating topological surface states

Dephasing length varies with temperature, revealing relaxation mechanisms

EEI effects support WAL analysis and channel coupling insights

Abstract

We report results of a magneto-transport study on thin films of the topological semi-metal candidate PdSb$_{2}$ (PS). We observe a positive correction to magneto-conductivity at low temperatures, which is a signature of weak anti-localization (WAL). We analyze the WAL data within the Hikami-Larkin-Nagaoka (HLN) theory and extract the dephasing length (L$_{\phi}$) whose temperature dependence reveals the various phase relaxation mechanisms. From the WAL effect, we also extract $\alpha$ (the number of transport channels). The evolution of $\alpha$ with temperature and film thickness reflects how the coupling between different conducting channels (Topological surface channels and bulk channels) changes. Additionally, the electron-electron interaction (EEI) effect was observed in the temperature-dependent conductivity at low temperatures. From the EEI effect, we get an alternate estimate of the number of transport channels and obtain a value similar to that obtained from the analysis of the WAL effect. This suggests that in disordered films, the EEI effect can be used to get information about the coupling of the topological surface states with each other and with bulk states.