Anisotropic hysteretic Hall-effect and magnetic control of chiral domains in the chiral spin states of Pr$_2$Ir$_2$O$_7$

TL;DR

This study reveals strong directional dependence in the anomalous Hall effect and magnetoresistance in Pr$_2$Ir$_2$O$_7$, linked to magnetic domain behavior and electronic structure changes under magnetic fields.

Contribution

It demonstrates the anisotropic hysteretic Hall effect and magnetoresistance in Pr$_2$Ir$_2$O$_7$, highlighting the role of magnetic domains and field-induced electronic structure reconstruction.

Findings

Hysteretic anomalous Hall effect below 1.5 K with field direction dependence.

Large positive magnetoresistance and Shubnikov de Haas oscillations along [111].

Field-induced growth of 3-in 1-out spin domains.

Abstract

We uncover a strong anisotropy in both the anomalous Hall effect (AHE) and the magnetoresistance of the chiral spin states of Pr$_2$Ir$_2$O$_7$. The AHE appearing below 1.5 K at zero magnetic field shows hysteresis which is most pronounced for fields cycled along the [111] direction. This hysteresis is compatible with the field-induced growth of domains composed by the 3-in 1-out spin states which remain coexisting with the 2-in 2-out spin ice manifold once the field is removed. Only for fields applied along the [111] direction, we observe a large positive magnetoresistance and Shubnikov de Haas oscillations above a metamagnetic critical field. These observations suggest the reconstruction of the electronic structure of the conduction electrons by the field-induced spin-texture.