Grant: Alliance Grants

The path to building a fault-tolerant quantum computer is paved with several important hurdles that must be overcome before reaching a regime where these machines will provide a technological advantage. Most of these challenges are linked to the extreme difficulty to scale processors and their related hardware efficiently, robustly and cost-efficiently. The goal of this project is precisely to participate in the worldwide effort to develop a hardware-efficient platform for quantum computing based on the technology of superconducting circuits. More specfically, our project involves three original and synergetic research axes: 1- Engineer and characterize more robust qubit architectures inspired from topological phases of matter, namely Majorana fermions and parafermions, whose intrinsic resilience to external noise will provide enhanced protection against decoherence. This axis will first involve classical simulation of simpler models on high-performance comupting platforms, then quantum simulation on real-life noisy intermediate-scale quantum computers built by one of the partner organization and operated by the other. 2- Develop and implement advanced computing methods inspired from machine learning to control and readout more efficiently highly complex quantum states on the processor. As the number of qubit on the processor increases (notably in the first axis), the complexity of calibration, control and readout procedures will increases exponentially. We will thus develop advanced techniques to efficiently realize these procedures. 3- Build and optimize optoelectronic systems to control the qubits' state with optical fields that require a reduced footpring. Presently, superconducting circuits are controlled with cryo-compatible electrical cables that are fragile, expensive and very difficult to industrially scale. By multiplexing the information in optical field, we will be able to critically reduce this hardware footprint and open the possibility to entangle remote machines. More specifically, in this project, we will develop fiber Bragg gratings acting as optical resonators that will be coupled to superconducting circuits and controlled externallly at room temperature. Each of these milestones, individually, will represent critical breakthroughs toward the realization of a fault-tolerant scalable quantum computer. This will have an important impact on the academic and industrial development of Canada in areas that will highly benefit from such a disruptive technological asset: cryptography and secure communications, optimization problems, advanced material simulation, fundamental research... In order to tackle these ambitious milestones, we have gathered a balanced and highly competent team of researchers (involving two theoreticians and two experimentalists) and well-established partner organizations in the field of quantum computing - Anyon Systems and Calcul Québec - who respectively manufactures and operates real-life quantum processors. Hence, this project will allow these organizations to advance their research and development program by harnessing the fundamental and diverse expertise of the academic team, thus consolidating their leadership position in Canada and worldwide. Moreover, it will provide a unique training experience in the quantum industry for graduate students and postdocs