Quantum oscillations and weak anisotropic resistivity in the chiral Fermion semimetal PdGa

TL;DR

This study investigates the magnetotransport properties and quantum oscillations in PdGa, a chiral Fermion semimetal, revealing its multi-band nature, weak resistivity anisotropy, and Fermi surface characteristics consistent with theoretical predictions.

Contribution

It provides detailed experimental analysis of quantum oscillations and magnetoresistance in PdGa, confirming theoretical Fermi surface models and revealing its multi-band, weakly anisotropic electronic structure.

Findings

PdGa exhibits unsaturated quadratic magnetoresistance.

Quantum oscillation frequencies match Fermi surface calculations.

Resistivity shows weak anisotropy with specific symmetry patterns.

Abstract

We perform a detailed analysis of the magnetotransport and de Haas-van Alphen (dHvA) oscillations in crystal PdGa which is predicted to be a typical chiral Fermion semimetal from CoSi family holding a large Chern number. The unsaturated quadratic magnetoresistance (MR) and nonlinear Hall resistivity indicate that PdGa is a multi-band system without electron-hole compensation. Angle-dependent resistivity in PdGa shows weak anisotropy with twofold or threefold symmetry when the magnetic field rotates within the (1$\bar{1}$0) or (111) plane perpendicular to the current. Nine or three frequencies are extracted after the fast Fourier-transform analysis (FFT) of the dHvA oscillations with B//[001] or B//[011], respectively, which is confirmed to be consistent with the Fermi surfaces (FSs) obtained from first-principles calculations with spin-orbit coupling (SOC) considered.