Ligand Mediated Magnetoelectronic Coupling Across Metamagnetic Transitions in CrPS4

TL;DR

This study investigates the complex magnetoelectronic coupling in CrPS4, revealing how extended superexchange interactions influence its magnetic phases and electronic states, with implications for phase engineering.

Contribution

It combines advanced spectroscopic techniques and quantum calculations to uncover the hybridized electronic states and superexchange pathways in CrPS4's magnetic phases.

Findings

Identified hybridization between crystal-field and charge-transfer transitions.

Revealed superexchange pathways involving P and S atoms.

Elucidated electronic states across magnetic phases.

Abstract

Chromium thiophosphate is a long-known material: a layered semiconducting antiferromagnet. Its recently discovered gate-tunable metamagnetic phase transitions, the remarkable positive and oscillating magnetoresistance as a tunnel barrier, and its Fano-resonance luminescence, elusive among the multitude of Cr3+ compounds, call for revisiting the understanding of its electronic structure, especially regarding how it relates to magnetic order. Here, we employ X-ray magnetic circular dichroism, implemented in both absorption and resonant inelastic X-ray spectroscopies, together with quantum many-body calculations, to unveil the complex nature of magnetoelectronic coupling in CrPS4, featuring hybridization between crystal-field and charge-transfer transitions. We reveal the role of extended superexchange paths involving P and S atoms, mediating interactions between the Cr spins across the different magnetic phases: antiferromagnetic, canted, and ferromagnetic. Our results elucidate the electronic states involved in these phases and provide prescriptions for engineering the metamagnetic phase diagram of CrPS4.