Conventional computers and communication networks are encountering stringent limits on performance and scalability. There is an increasing need to reduce the energy costs of data processing, storage and communications, as well as for guaranteed security and authentication in both communication and computation systems. Quantum technologies offer a viable "Beyond-Moore's-Law" strategy, especially in communications and information processing, where quantum optics has clearly demonstrated beyond-classical advantages in a number of landmark experiments. But the traditional approach of quantum optics relies on table-top laboratory experiments usually conducted at extremely low temperatures, and requiring large and expensive ancillary equipment for successful operation. These constraints inhibit the transition of quantum optics research into practical applications and everyday usage. This project will use the same technology as used to make integrated circuits in the electronics industry today to develop a new generation of energy-efficient, non-cryogenically cooled microchips for secure and efficient optical communications. Development of these microchips will also benefit sensors and standards calibration, metrology, and low-light-level imaging. The transition of laboratory research to real-world applications will be helped by leveraging scalable and cost-effective foundry-based manufacturing technologies to make devices. Research collaborations with industry and government laboratories will provide broader perspective as well as scope for field applications and student mentoring. The project will also support the development and dissemination of educational modules that introduce quantum mechanics through optics for high schools (including material for laboratory experiments) and undergraduate students, including future engineers who traditionally have not learnt about quantum mechanics and its potential engineering applications.
The technical goal of this project is to design, fabricate and demonstrate microchips for quantum communications using entanglement over conventional optical fiber. Research will focus on creating ultra-compact (centimeter-scale) microchips which miniaturize previous table-top or bread-board apparatus for generating and detecting entangled, heralded and single photons, for quantum memories without requiring cryogenic cooling, and for demonstrations of quantum key distribution protocols. Scalable manufacturing techniques based on established micro-electronics foundry platforms will be utilized, which may result in reducing the cost and mitigating some of the risks of making greater quantities of devices for practical applications. Integrated pair-generation and single photon devices will be designed for encoding time-bin information with gigahertz-rate clocking. Key linear optical quantum information processing devices will be designed, such as up-conversion devices, uncooled waveguide-coupled quantum memory using storage and retrieval of photons, and an electro-optically switched recirculating loop which combines both planar and fiber technology and enables synchronization of photons over long relative delays. Microchips will be characterized in a fiber-based testbed for demonstrating the protocol of measurement device independent quantum key distribution. Many of these components and measurements will be also useful for a future fully-integrated quantum repeater in optically connected communication networks.
