Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

Our extensive experience in designing, fabricating, and optically manipulating planar-waveguide-based photonic circuits using silicon-on-insulator wafers operating at wavelengths near 1.5 µm will guide the development of similar circuits to be used at an operating wavelength of ~ 2.9 µm. This is motivated by one of the most exciting potential applications of silicon photonic circuitry, namely quantum information processing, and in particular by the recent discovery of optically active single atom-impurity sites in silicon that should, when combined with the elements we have previously developed, enable quantum logic to be performed using particles of light - photons - to manipulate and communicate the quantum state of these impurity atoms. The approach is well-suited for scaling up to include the number of building blocks (impurity atoms) needed to demonstrate the predicted superiority of quantum information processing as compared to the digital, classical information processing that pervades current society.

The key sub-components of these circuits are ultra-compact 3-dimensional optical microcavities within which individually trapped single photons can coherently interact with the electronic states of the co-located atomic impurity. These cavities have to contain the trapped photons for 100's of thousands of optical cycles in order for the electronic states and photons to efficiently couple. Cavities with the required properties have not yet been demonstrated at wavelengths ~ 2.9 µm. The other key ingredients are the atomic impurity states themselves, so called "deep donors", such as S or Se. Researchers at Simon Fraser University have shown that information encoded in the electronic spin state of donor impurities in silicon can be stored for times longer than any previously reported solid state system, long enough to enable effective quantum information processing, so long as methods are found to couple distinct impurity atoms. Our approach is to use 2.9 µm wavelength photons, routed using silicon photonic waveguides, to communicate this quantum information between atoms placed within the high quality microcavities discussed above.

If successful, this technology will potentially open one of the most exciting pathways towards a truly scalable quantum information processing platform. It could revolutionize quantum cryptography and quantum communication protocols in the shorter term, while possibly supporting full, universal quantum computation in the longer term. Quantum information processing itself represents one of the potentially revolutionary, game-changing technologies of this century.