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Controllable chirality-induced geometrical Hall effect in a frustrated highly correlated metal
B G Ueland1, C F Miclea, Yasuyuki Kato
1Los Alamos National Laboratory, Los Alamos, New Mexico 87544, USA. bgueland@lanl.gov
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. Here we show that the highly correlated metal UCu(5) possesses an unusually large controllable geometrical Hall effect at T<1.2 K due to its frustration-induced magnetic order. The magnitude of the Hall response exceeds 20% of the ν=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 UCu(5) opens a new field of enquiry into the importance of the role of frustration in highly correlated electron materials.
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