Observation of surface dominated topological transport in strained semimetallic ErPdBi thin films
Journal article, 2020

In this Letter, we present experimental observation of surface-dominated transport properties in [110]-oriented strained (∼1.6%) ErPdBi thin films. The resistivity data show typical semi-metallic behavior in the temperature range of 3 K ≤ T ≤ 350 K with a transition from semiconductor- to metal-like behavior below 3 K. The metallic behavior at low temperature disappears entirely in the presence of an external magnetic field >1 T. The weak-antilocalization (WAL) effect is observed in magneto-conductance data in the low magnetic field region and follows the Hikami-Larkin-Nagaoka (HLN) model. HLN fitting estimated single coherent channel, i.e., α ∼-0.51 at 1.9 K, and the phase coherence length (Lφ) shows the Lφ ∼T-0.52 power law dependence on temperature in the range of 1.9 K-10 K, indicating the observation of 2D WAL. Shubnikov-de Haas (SdH) oscillations are observed in magneto-resistance data below 10 K and are fitted to standard Lifhsitz Kosevich theory. Fitting reveals the effective mass of charge carriers ∼0.15 me and a finite Berry phase of 0.86π± 0.16. The sheet carrier concentration and mobility of carriers estimated using SdH data are ns ∼1.35 × 1012 cm-2 and μs = 1210 cm2 V-1 s-1, respectively, and match well with the data measured using the Hall measurement at 1.9 K to be n ∼1.22 × 1012 cm-2, μ = 1035 cm2 V-1 s-1. These findings indicate the non-trivial nature and surface-dominated transport properties of strained (110) ErPdBi thin films at low temperatures.

Author

Vishal Bhardwaj

Indian Institute of Technology

Anupam Bhattacharya

Indian Institute of Technology

A. K. Nigam

Tata Institute of Fundamental Research

Saroj Prasad Dash

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Ratnamala Chatterjee

Indian Institute of Technology

Applied Physics Letters

0003-6951 (ISSN) 1077-3118 (eISSN)

Vol. 117 13 132406

Subject Categories

Inorganic Chemistry

Other Materials Engineering

Condensed Matter Physics

DOI

10.1063/5.0023286

More information

Latest update

5/29/2024