Simultaneous achievement of record-breaking colossal magnetoresistance and angular magnetoresistance in an antiferromagnetic semiconductor EuSe2

TL;DR

This paper reports record-breaking colossal and angular magnetoresistance in EuSe2, an antiferromagnetic semiconductor, driven by magnetic field-induced phase transition and magnetic anisotropy, with implications for spintronic devices.

Contribution

It demonstrates simultaneous colossal and angular magnetoresistance in EuSe2, a novel antiferromagnetic material, supported by experimental and theoretical analysis.

Findings

Record-breaking CMR of ~ -10^14%

AMR of ~ 10^14% achieved

Magnetoresistance linked to magnetic phase transition

Abstract

Magnetoresistance effect lays the foundation for spintronics, magnetic sensors and hard drives. The pursuit of magnetic materials with colossal magnetoresistance (CMR) and/or angular magnetoresistance (AMR) has attracted enduring research interest and extensive investigations over past decades. Here we report on the discovery of field-induced record-breaking CMR of ~ -10^14 % and AMR ~ 10^14% achieved simultaneously in an antiferromagnetic rare-earth dichalcogenide EuSe2. Such intriguing observations are attributed to strong magnetic anisotropy and magnetic-field induced antiferromagnetic to ferromagnetic transition of the localized Eu2+ spins, which in turn closes the bandgap by lifting the degeneracy of Se-5p bands near Fermi level. Our DFT calculations perfectly replicate the experimental findings based on the Brillouin function and carries transport model. The present work provides a potential simple antiferromagnetic material for achieving angle-sensitive spintronic devices.