Magnetochiral Anisotropy Induced Nonreciprocal Transport in Si/SiOx/ZnO Heterostructures: A Path to Advanced Rectification and Spintronics

Abstract

Although magnetochiral-anisotropy-induced NCT has been largely restricted to in-plane magnetic fields, we demonstrate NCT response across both in-plane and out-of-plane directions in a Si/SiOx/ZnO heterostructure. The magnitude and behaviour of the NCT response, and the associated bilinear and quadratic magnetoresistance in Si/SiOₓ/ZnO heterostructures are highly sensitive to a complex interplay among thermal effects, magnetic field orientation and strength, and the structural properties of the ZnO film. The relative amplitudes of bilinear and quadratic magnetoresistance reveal the transition from classical to quantum-dominated transport, governed by the interplay of temperature, field strength, and magnetic field orientation. NCT is a rectification phenomenon that enables precise modulation of unidirectional conduction; however, it is traditionally forbidden in centrosymmetric systems. A standardized NCT coefficient (γ') of 3.6 × 10⁻⁷ A ^-1 T ^-1 m² in a meticulously engineered Si/SiOx/5.6 nm ZnO heterostructure at 160 K. The observed pronounced NCT in these heterostructures arises from structural inversion asymmetry and asymmetric skew scattering, which generates Rashba spin-orbit coupling, spin-momentum locking, chiral transport and a two-dimensional electron gas at the SiOx-ZnO interface. The robust and tunable NCT response in all three orientations demonstrated here paves the way for advanced vector magnetic field sensors and integrated micro-rectifiers capable of precise directional discrimination in complex electromagnetic environments.