Anomalous magnetotransport in the single-crystalline half-Heusler antiferromagnet ErPdSb

TL;DR

This study investigates the magnetic, electronic, and transport properties of single-crystalline ErPdSb, revealing antiferromagnetic order, semimetallic behavior, and complex magnetoresistance effects, with potential Fermi surface reconstruction under magnetic fields.

Contribution

It provides comprehensive experimental and theoretical insights into ErPdSb's magnetotransport and electronic structure, highlighting novel magnetic and transport phenomena in this half-Heusler antiferromagnet.

Findings

Antiferromagnetic order at 1.2 K.

Semimetallic behavior with resistivity hump around 70 K.

Unusual angular magnetoresistance indicating Fermi surface changes.

Abstract

We report the thermodynamic and magnetotransport properties of the half-Heusler antimonide ErPdSb, studied on single-crystalline samples in wide ranges of temperature and magnetic fields. The compound was found to order antiferromagnetically at 1.2 K. In the paramagnetic state, it shows semimetallic behavior with a broad hump in the temperature-dependent electrical resistivity around 70 K. The results of ab initio calculations of the electronic structure of ErPdSb indicated a bulk insulating nature. In small magnetic fields the magnetoresistance is driven by a weak antilocalization effect, while in strong fields it is negative and describable by the deGennes-Friedel formalism. The Hall effect data indicated that holes are the dominant charge carriers. At 2 K, the Hall conductivity exhibits a sizable anomalous contribution, which is obscured by multiband effects at higher temperatures. The angular magnetoresistance shows unusual features as functions of magnetic field and temperature, pointing to a possible field-induced reconstruction of the Fermi surface.