Quantized piezospintronic effect in antiferromagnetic Moiré systems
摘要
This paper presents a novel approach for generating and controlling spin currents in an antiferromagnetic twisted honeycomb bilayer in response to elastic deformation. Using a continuum model based on the Bistritzer–MacDonald model that captures the physics of low-energy moiré bands, we calculate the spin-current response in the Berry-phase formalism. The resulting moiré superlattice potential modulates the electronic band structure, leading to emergent topological phases and novel transport properties such as quantized piezo responses both for spin and charge transport. This approach allows us to tune the system across different topological regimes and to explore the piezo-spintronic responses as a function of the band topology. When inversion symmetry is broken either by a sublattice potential V, alignment with an hBN substrate, uniaxial strain, or structural asymmetry present in the moiré superlattice, the system acquires a finite Berry curvature that is opposite in the K and