Grant: Alliance Grants

Quantum computing has been developed in two parallel paradigms: continuous variable (CV) and discrete variable (DV). These approaches require different sources: Squeezed light sources (SLSs) for the former and single photon sources (SPSs) for the later. Both types of source carry quantum information and can be used for quantum communications, computing, and sensing. There is a strong need to develop reliable and practical sources for both types of processing. The characteristics of spontaneously emitted photons, in a SLS or a SPS, depend critically on the electromagnetic environment (optical density of states) into which emission happens. By controlling this environment, characteristics such as the polarization, propagation direction and rate of emission can be controlled. For example, if a single emitter is placed in a cavity resonant at the spontaneous emission wavelength, the emission rate can be enhanced (Purcell effect). Enhancing the emission rate leads to brighter (higher count) single photon sources and to improved indistinguishability by beating the decoherence of the system. Furthermore, emission occurs into a well-defined mode of the cavity thereby imparting on single photons the characteristics of the mode (e.g., field distribution, polarization). We propose plasmonic nano-antennas integrated with 2D materials such as graphene and hexagonal boron nitride (hBN) to realise SLSs via four wave mixing and SPSs via defect engineering. We propose to integrate the sources on silicon nitride waveguides and optimize their emission into the TE or TM modes of the waveguide via careful antenna design. We aim to enable an integrated quantum photonics platform useful for quantum communications and computing.