Controllable chirality-induced geometrical Hall effect in a frustrated highly-correlated metal

TL;DR

This paper demonstrates a large, controllable geometrical Hall effect in the frustrated, highly-correlated metal UCu5 at low temperatures, driven by non-coplanar magnetic order and independent of spin-orbit coupling.

Contribution

It reveals the significant role of magnetic frustration in inducing a large geometrical Hall effect in a correlated metal, expanding understanding of topological transport phenomena.

Findings

Hall response exceeds 20% of quantum Hall effect per atomic layer

Effective magnetic field of several hundred Tesla on electrons

Large controllable geometrical Hall effect observed in UCu5 at T<1.2K

Abstract

A current of electrons traversing a landscape of localized spins possessing non-coplanar magnetic order gains a geometrical (Berry) phase which can lead to a Hall voltage independent of the spin-orbit coupling within the material--a geometrical Hall effect. We show that the highly-correlated metal UCu5 possesses an unusually large controllable geometrical Hall effect at T<1.2K due to its frustration-induced magnetic order. The magnitude of the Hall response exceeds 20% of the \nu=1 quantum Hall effect per atomic layer, which translates into an effective magnetic field of several hundred Tesla acting on the electrons. The existence of such a large geometric Hall response in UCu5 opens a new field of inquiry into the importance of the role of frustration in highly-correlated electron materials.