Grant: Alliance Grants

Quantum networks can provide a revolutionary solution to our society's need for secure communication, as required, e.g., in the transmission of personal, bank, and government data. A quantum communication network consists of integrated local nodes allowing the generation of optical quantum states through single- and two-photon entangled sources, as well as their long-term storage through quantum memories. Photons are then shared among distant partners through a fiber-optic infrastructure connecting the local quantum nodes. Several approaches have been explored to realize integrated local nodes; quantum dots for single-photon sources, Chi(3) materials (e.g., Hydex glass) for two-photon sources, and spin-active impurities for quantum memories. However, two main bottlenecks prevent the development of quantum networks: (i) photon losses and (ii) the lack of a robust interconnection between the local nodes. The only way to achieve long-distance quantum communications is to minimize optical losses stemming from the network components. In this proposal, the PI aims, with the support of the industrial partner OEC, to develop low-loss and robust interconnects between integrated waveguide-based photonic chips and standard optical fibers, a crucial milestone towards the commercialization of fiber-based quantum secure communications. To this end, we will deliver (I) a microring resonator capable of generating high-dimensional frequency entangled photon pairs with novel enhanced coupling efficiency and performances, (II) low-loss photon processing schemes based on off-the-shelf fiber-based components, and (III) superconducting nanowire single-photon detectors with high-detection efficiency and optimized for coupling to different material platforms. This proposal features an extensive collaboration with UK academic and industrial teams, who will develop in parallel SiN-based photonics chips, as well as photon emitters and quantum memories. The targeted outcomes will benefit Canadian industry through the training of highly qualified personnel in the fields of integrated photonics and device design and will contribute to maintain Canada as a leading player in the quantum secure communication market.