Anomalous inverse Faraday effect for graphene quantum dots in optical vortices
Abstract
Chiral photon interactions with two-dimensional (2D) materials enable unprecedented control of quantum phenomena. In this paper, we report anomalous inverse Faraday effects (IFE) in graphene quantum dots (GQDs) under linearly polarized optical vortex illumination, where transferred orbital angular momentum (OAM) generates light-induced magnetic moments. Employing our recently developed time-dependent quantum perturbation framework [Phys. Rev. B 110, 085425 (2024)], we demonstrate a counterintuitive observation: some reversed magnetic moments at off-axis positions occur-manifested as counter-rotating currents to the vortex helical wavefront. Phase-difference analysis and eigenmode decomposition resolve this anomaly, revealing that the OAM transfer efficiency is orders of magnitude weaker than its spin counterpart. This work establishes a new paradigm for optical OAM-to-magnetization conversion in quantum-engineered 2D systems.