Grant: Research Tools and Instruments - Category 1 (<$150,000)

Entanglement is the one of the strangest consequences of quantum mechanics and the basis for a wide range of exciting new technologies. These technologies promise to transform the way we communicate and process information through the ultimate security of quantum cryptography to the super-fast algorithms of quantum computing. Thanks to funding from the Ontario Centres of Excellence (OCE), we are focusing on building next-generation sources of entangled photons, the fundamental particles of light. These sources promise dramatic improvements to brightness and entanglement. Improving these qualities directly impact quantum technologies, offering higher bit rates in cryptography and lower errors in computation. We will demonstrate the effectiveness of these sources in our free-space quantum cryptography prototype connecting the Institute for Quantum Computing to the Perimeter Institute nearly 2km away. This application is requesting funding for diagnostic equipment, not covered by the OCE, to enable accurate characterization of these sources. The equipment requested comprises two spectral characterization systems. The first piece of equipment is a high-efficiency, high-resolution, low-noise spectrometer. This system will allow rapid accumulation of the intensity spectrum of the light produced in our sources. This data will be used to align and optimize the parameters in the sources to maximize brightness in the correct spectral window. The second piece of equipment is a single-photon counting dual monochromator. This device will be used to measure the correlations in the frequencies of the pairs of photons in our sources. This information is extremely important in advanced quantum protocols, such as quantum teleportation. The spectrometer will be used by two graduate students and a post-doctoral researcher. The dual monochromator will be built and tested by undergraduate co-op and fourth year students.