Antiferromagnetic metal phase in an electron-doped rare-earth nickelate

TL;DR

This study reveals a novel electron-doped metallic phase in NdNiO3 with preserved magnetic order, electronic reconstruction, and potential for spintronic applications, expanding the understanding of rare-earth nickelates.

Contribution

It demonstrates the emergence of a metallic phase in NdNiO3 upon low electron doping, with preserved magnetic order and controllable spin structures.

Findings

Electron doping induces a metallic phase in NdNiO3.

The metallic phase exhibits a Fermi surface mostly gapped by electronic reconstruction.

Large zero-field planar Hall effect enables spin structure read/write operations.

Abstract

Long viewed as passive elements, antiferromagnetic materials have emerged as promising candidates for spintronic devices due to their insensitivity to external fields and potential for high-speed switching. Recent work exploiting spin and orbital effects has identified ways to electrically control and probe the spins in metallic antiferromagnets, especially in noncollinear or noncentrosymmetric spin structures. The rare earth nickelate NdNiO3 is known to be a noncollinear antiferromagnet where the onset of antiferromagnetic ordering is concomitant with a transition to an insulating state. Here, we find that for low electron doping, the magnetic order on the nickel site is preserved while electronically a new metallic phase is induced. We show that this metallic phase has a Fermi surface that is mostly gapped by an electronic reconstruction driven by the bond disproportionation. Furthermore, we demonstrate the ability to write to and read from the spin structure via a large zero-field planar Hall effect. Our results expand the already rich phase diagram of the rare-earth nickelates and may enable spintronics applications in this family of correlated oxides.