Current-sensitive Hall effect in a chiral-orbital-current state.

Chiral orbital currents (COC) underpin a novel colossal magnetoresistance in ferrimagnetic Mn 3 Si 2 Te 6 . Here we report the Hall effect in the COC state which exhibits the following unprecedented features: (1) A sharp, current-sensitive peak in the magnetic field dependence of the Hall resistivity, and (2) A current-sensitive scaling relation between the Hall conductivity σ xy and the longitudinal conductivity σ xx , namely, σ xy ∝ σ xx α with α reaching up to 5, which is exceptionally large compared to α ≤ 2 typical of all solids. The novel Hall responses along with a current-sensitive carrier density and a large Hall angle of 15% point to a giant, current-sensitive Hall effect that is unique to the COC state. Here, we show that a magnetic field induced by the fully developed COC combines with the applied magnetic field to exert the greatly enhanced transverse force on charge carriers, which dictates the COC Hall responses.