Stark control of plexcitonic states in incoherent quantum systems

Electro-optic control of quantum dots embedded in plasmonic nanocavities enables active tuning of photonic devices for emerging applications in quantum optics such as quantum information processing, entanglement, and ultrafast optical switching. Here, we demonstrate the coherent control of plexcitonic states in (i) off-resonant and (ii) resonant coupled quantum systems through the optical Stark effect. We analyze a hybrid plasmon-emitter system which exhibits tunable photoluminescence, Stark-induced transparency, and vacuum Rabi splitting due to a quadratic Stark shift in the degenerate states of a quantum emitter (QE). In addition, a resonantly coupled system shows path interference of hybrid plexcitonic states due to Stark-induced splitting in a two-level QE. Our study shows that the Stark tuning of plexcitons not only mitigates decoherence in the quantum system but it also stimulates the on/off / off switching of spontaneous photon emission in the visible regime. Such tunable systems can be used to operate photonic integrated circuits for applications in quantum computing and information processing.