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

Zhang, Yu; Ni, Yifei; Schlottmann, Pedro; Nandkishore, Rahul; DeLong, Lance E; Cao, Gang · Nat Commun · 2024

basic_science · Level V

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Abstract

Chiral orbital currents (COC) underpin a novel colossal magnetoresistance in ferrimagnetic Mn<sub>3</sub>Si<sub>2</sub>Te<sub>6</sub>. 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<sub>xy</sub> and the longitudinal conductivity σ<sub>xx</sub>, namely, σ<sub>xy</sub> ∝ σ<sub>xx</sub><sup>α</sup> 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.