Coherent quantum information platform with spin-orbit coupling in silicon

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Quantum computers and quantum simulators have the potential to perform computational tasks that are impossible on modern computers in areas like machine learning, optimisation, and simulation of materials and drugs. Realising this potential is considered a grand challenge in the sciences because it requires precise engineering and control of a large quantum system, while avoiding decoherence that destroys quantum effects and corrupts the computation. However, no single quantum bit (qubit), the building block of such systems, currently has the characteristics required to achieve this goal. The aim of my research program is to use silicon technology to demonstrate a quantum simulator that can shed new light on phenomena in quantum condensed matter physics, and a prototype general purpose quantum computer that overcomes the main obstacle for spin-based quantum computing, interconnecting many qubits on the same chip without sacrificing manufacturability. My experimental program will employ ultra-pure silicon materials, innovative low-temperature high magnetic field experiments, and collaboration with leading theoretical experts on controllable quantum systems. To achieve the first milestone, long-range electrically mediated coupling between spin-based qubits in silicon will be pursued. This will leverage my recent discovery that spin qubits can possess spin-orbit coupling enabling electrical qubit coupling while maintaining extremely long coherence times, characteristics previously thought to be incompatible. The key is to use hole spins where total angular momentum (not spin) is quantized. Electrical circuits and/or resonators will be employed control and interconnect the quantum bits to demonstrate electrically mediated entangling logic gates and optimise their accuracy, a major achievement for the field. The second milestone will be to develop a quantum simulator based on spin qubits to shed new light on the problem strongly correlated fermions in condensed matter physics that is hard to simulate classically, and hard to simulate quantum mechanically with other systems. This will leverage my recent discovery that spin qubits emulate the Fermionic behaviour making them uniquely suited to simulate a wide range of phenomena including unconventional superconductivity. Larger arrays of qubits with short range interactions will enable the first true Fermionic quantum simulators, while the long-range electrical interactions could open a pathway to simulate even more elusive phenomena. Successfully achieving these goals could propel Canada to lead the international race to build large-scale quantum technologies, and to reap a great share of the expected socio-economic benefits of a second information revolution based on quantum physics.