Controllable chirality-induced geometrical Hall effect in a frustrated   highly-correlated metal
  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. 
B. G. Ueland, C. F. Miclea, Yasuyuki Kato, O. Ayala-Valenzuela, R. D.   McDonald, R. Okazaki, P. H. Tobash, M. A. Torrez, F....
cond-mat.str-el