Research

 Quantum sensing 

We develop novel quantum sensing and imaging techniques based on spins in diamond, and explore applications to biology, chemistry and condensed matter physics. The physical system we use is the nitrogen-vacancy (NV) centre in diamond, an atomic defect that acts as a spin qubit embedded in a solid matrix. Importantly, the electrons trapped in the NV centre possess a spin that can be optically polarised, manipulated and read-out, even at room temperature. This allows spin resonances of a single NV centre to be detected by optical means, which forms the basis for quantum sensing protocols designed to detect minute magnetic fields, electric fields, or temperature variations. Our group theoretically and experimentally explores new quantum sensing and imaging techniques, with a focus on real-world applications across physical and life sciences. For an introduction to quantum sensing, check out this story and more.

Examples of recent projects:

Mapping band bending with in-situ quantum sensors

Published in Nature Electronics. See News & Views.

Quantum probe hyperpolarisation of molecular nuclear spins

Published in Nature Communications. See Press Release

Quantum imaging of current flow in graphene

Published in Science Advances. See Press release.

A quantum spin-probe molecular microscope

Published in Nature Communications. See Press release.

 

Quantum computing

We theoretically investigate quantum computing based on nuclear or electron spins, with a particular focus on isolated phosphorous impurities in silicon, which are promising candidates for the design of scalable quantum computer architectures. Our team develops state-of-the-art theoretical models to simulate quantum computing devices and circuits, providing critical guidance to collaborating experimental groups at the University of New South Wales, Sydney. In particular, we have developed a comprehensive theoretical framework based on atomistic tight-binding theory, which can compute both the single-particle and multi-particle electronic structure with several million atoms in the simulation domain. Recently our team has achieved a critical milestone towards the implementation of accurate quantum computer designs by enabling the exact pinpointing of qubit spatial locations in silicon based on scanning tunneling microscope imaging techniques. Another part of our work explores innovative quantum computing architectures. In particular, we have recently proposed a surface code quantum computer based on a two-dimensional lattice of donor spin qubits in silicon, providing a new pathway for large-scale quantum information processing in silicon. For an introduction to quantum computing, check out this video and more.

Examples of recent projects:

Simulations of Shor’s algorithm up to 60 qubits

Published in Quantum. See Press release. ABC radio AM.

Entanglement in a 20-qubit quantum computer

Preprint.

A surface code quantum computer in silicon

Published in Science Advances. See Video.

Pinpointing qubits in a silicon quantum computer

Published in Nature Nanotechnology. See Video.