Room-Temperature Generation of Indistinguishable Single Photons

Can a stream of indistinguishable single photons be generated at room temperature? Yes, if the quantum emitter (QE) generates photons before it interacts with phonons that influences the photon emission frequency. At room temperature the phonon interaction time is ~10^(-14) s, while the typical emission time is 10^(-8) s, which is one million times larger! It is known that the emission time can be decreased via the Purcell effect by creating a suitable photonic environment, but current records of the Purcell enhancement (<10000) fall short of reaching the required threshold of enhancement by 2 orders of magnitude. In this project, the emission-rate of a special QE (Group IV color center in a nanodiamond, which interacts less with phonons due to its position in the lattice) will be enhanced by utilizing a combination of a gap-plasmonic structure with ultra-small gaps (<2 nm) and a dielectric cavity. This combination will provide us with the necessary enhancement in emission rate to make it larger than its rate of interaction with phonons at room temperature. In addition to generating indistinguishable photons, it will also make the communication between quantum nodes faster than terabits/s. Therefore, the proposed project will solve two issues that current quantum technologies face – 1. Requirement of cryogenic temperatures and 2. Low rate of single photon generation. This will pave the way for quantum networks and quantum computers based on photonic technologies operating at room temperature.