Orbital Longitudinal Magnetoelectricity in Quasi-2D Parity-Violating Antiferromagnets: Interplay of Berry Phase and Stacking Order

Abstract

In this work, we propose an intrinsic mechanism for longitudinal magnetoelectric (ME) coupling in quasi-2D antiferromagnets that lack spatial inversion symmetry. We demonstrate that in such parity-violating antiferromagnets, the stacking order, when coupled with Berry curvature and orbital magnetic moment, generates a stacking Berry curvature dipole (SBCD) and a stacking orbital magnetic moment dipole (SOMD). The SBCD and SOMD act as the fundamental ingredients of the longitudinal ME response. As concrete examples, we apply our framework to typical parity-violating antiferromagnets with stacking magnetic orders. Furthermore, the SBCD is also identified as the origin of electric-field-induced Hall effects. Our results reveal the microscopic orbital origin of the ME effect in antiferromagnetic systems with vanishing net Berry curvature and orbital magnetization, governed by the interplay between Berry phase effects and layer stacking orders.

8 pages, 6 figures