Optical Transparency near a MoS₂ Nanodisk

Electromagnetically induced transparency (EIT) is an important quantum coherence and interference phenomenon in optical and photonic structures. The typical system for EIT involves a three-level, Λ-type, quantum system that interacts coherently with two electromagnetic fields, a weak probe field and a strong coupling field, which individually drive the two allowed electronic transitions of the quantum system. The presence of the coupling field leads to optical transparency of the probe field, which couples the adjacent transition in the quantum system. An interesting alternative of EIT is vacuum induced transparency (VIT), where the external coupling field is replaced by strong coupling with a modified cavity vacuum. VIT has been experimentally realized for atoms in an optical cavity, and has been predicted to occur for quantum systems embedded in other photonic structures, like, for example, photonic crystals, polaritonic-photonic crystal nanofibers, and metamaterials. Here, we show that the strong coupling at the nanoscale, which can occur when a quantum system is placed near a photonic nanostructure, can also lead to VIT. As an example, we study the case where a three-level quantum system is placed near a MoS₂ nanodisk. It has been recently shown that the localized exciton-polariton modes occurring in the MoS₂ nanodisk lead to sharp and high peaks in the Purcell enhancement factor spectrum, leading to strong-light matter coupling with nearby quantum systems. In this work, we show that this effect also leads to VIT in a three-level quantum placed near the MoS₂ nanodisk. We also find that we may obtain either single or multiple VIT effects, depending on the distance between the quantum system and the MoS₂ nanodisk, the radius of the MoS₂ nanodisk, and the free-space decay rate of the quantum system transition at which the strong light-matter coupling occurs.