Manipulating spatially distributed absorption effects in the atomic configuration of mercury with orbital angular...

In this paper, we investigate the spatially dependent absorption characteristics of a four-level atomic mercury system interacting with optical vortex beams carrying orbital angular momentum (OAM). By measuring the imaginary part of the susceptibility of the probe field, we explore the effects of various configurations of control fields on the absorption profile. Initially, we examine the case with a single-composite OAM beam, observing that regions of reduced absorption form flower-like petal patterns, which become more pronounced with increasing OAM values. Introducing a second composite beam with matching or differing OAM values significantly modifies these patterns, leading to enhanced control over the spatial distribution of absorption and transparency. Additionally, we consider the impact of an incoherent pumping field on the transition. Our findings show that the incoherent pumping field further refines the absorption patterns, enabling precise control over the spatial zones of high and low transmission. This effect is particularly pronounced in non-resonant conditions, where the spatial distribution of transparency and absorption can be finely tuned by modifying the OAM characteristics of the composite beams. These results demonstrate the potential of using OAM composite beams and incoherent pumping fields to manipulate light-matter interactions at the quantum level, with applications in high-resolution imaging, quantum information storage, and the creation of complex optical traps for atomic systems.