Collaborative research drives towards 100 qubit system

In conversation with IQC researcher David Cory, Canada Excellence Research Chair

Quantum sensors, actuators, communication systems and computers will greatly impact our world. We have already seen quantum sensors provide more sensitivity and specificity than their classical counterparts. These quantum sensors are developed and deployed for important societal problems, for example, in relation to neutron studies of materials and to the oil industry for geological exploration. The sensors demonstrated so far use quantum algorithms and control methods with small quantum processors and find applications as far-reaching as metrology, fuel cell development, medicine and exploring Standard Model physics. Despite using only a single part of the overall quantum promise, these advances have been game changing.

These powerful advances are achieved with small systems and the quantum advantage is tied primarily to preserving coherence over a few qubits. The full impact of quantum information processing relies on having coherent control over larger systems of quantum particles where the Hilbert space is so complex that comparison to classical systems is meaningless. Recall that to fully simulate the dynamics of even 30 qubits is beyond the ability of any classical processor.

We are in the midst of a project to build a larger scale quantum processor by combining spin systems, superconducting electronics and qubits into one “hybrid” quantum processor. Nuclear and electron spin systems remain the most coherent and largest experimentally proven systems. Superconducting systems of qubits are the most flexible quantum systems and are open to easy engineering. Our research program aims to develop hybrid quantum processors where electron spins serve as quantum actuators, nuclear spins serve as qubits and superconducting circuits are the control and measurement apparatus for the electron spins. We plan for this processor to be about 100 physical qubits. It will enable us to explore how to control large processors, how to implement quantum error correction and provide a start to using quantum computers as non-trivial simulators of quantum physics.

The hybrid nature requires a broad range of expertise. Researchers are working together to explore the hybrid systems through experiments with low temperature and spin physics, as well as control theory and quantum information theory. This work brings together chemistry, physics, electrical engineering, math and computer science to effectively integrate this knowledge and apply it to one big goal — a 100 qubit quantum computer.