Twisted light drives chiral excitations of interacting electrons in nanostructures with magnetic field

Abstract

Twisted light (TL), a special kind of light carrying orbital angular momentum, provides a powerful tool for driving symmetry resolved transitions in quantum confined nanostructures. We study a realistic model where a TL pulse excites two interacting electrons in a nanostructure under a perpendicular magnetic field. To include image charge effects in layered systems, we use an effective electron electron potential of the form 1/r^n. For n = 2, the system exhibits an underlying su(1,1) dynamical symmetry, enabling analytical solutions and a clear interpretation of selection rules, parity changes, and angular momentum resolved absorption. We show that the bare Coulomb 1/r interaction produces similar spectra, indicating that twisted light driven excitations are robust against the precise interaction form. The excitation spectrum reveals strong chiral properties: TL pulses, unlike conventional dipolar fields, directly access interaction-driven transitions otherwise symmetry-forbidden. In particular, TL breaks the generalized Kohn theorem, exposing internal excitations through multi quanta orbital processes. More broadly, our results establish TL as a sensitive probe of correlations, symmetry, and magneto-optical dynamics in strongly interacting quantum systems, uncovering features that remain invisible to standard infrared absorption.