World-leading research on quantum computing

Dr Longdell's research group. From left to right: Dr Jevon Longdell, Group Leader; Xavier Fernandez, PhD Student; Maddy Cormack, PhD Student: Jelena Rakonjac, Honours Student; Dr Stephen Chen, Postdoctoral researcher.

Dr Longdell’s research group. From left to right: Dr Jevon Longdell, Group Leader; Xavier Fernandez, PhD Student; Maddy Cormack, PhD Student: Jelena Rakonjac, Honours Student; Dr Stephen Chen, Postdoctoral researcher.

Remarkable progress has been made towards quantum computing in recent years, and in the future such computers will be able to solve problems considerably quickly than any classical computer.

Quantum computers are unique in that binary numbers are stored in “qubits”, a unit of information that can store not only zeroes and ones but also combinations of both. One of the most promising qubit technologies are based on nanoscopic circuits made with superconducting metals.

However, these “superconducting qubits” currently have two major weaknesses; they are unable to store information for a useful length of time, and they lack a mechanism for long distance communication. In an attempt to resolve these issues qubits have been coupled to other devices, but with minimal success.

Dr Jevon Longdell, from the University of Otago, with world-leading researchers from Japan and Australia, will study crystals doped with rare earth elements, such as europium and erbium, to add long term memory to qubits. The rare earth elements introduce magnetism to the crystal, which will be investigated in various ways to enhance memory, and to allow qubits to communicate with each other over large distances.

This topic is very timely and has high scientific interest given the enormous effort world-wide that is aimed at building a superconducting, qubit-based, quantum computer.

Show light from a dye laser interacting with a rare earth ion doped crystal. The laser beams outside the crystal were made visible using an artificial "fog" using a stream of very cold gas.

Light from a dye laser interacting with a rare earth ion doped crystal. The laser beams outside the crystal were made visible using an artificial “fog” using a stream of very cold gas.

Total Funding: $790,000 (excl. GST, paid out over 3 years)

Including: salaries (these include post-doctoral fellowships and postgraduate stipends where applicable), overheads, expendable costs

Principal Researcher: Dr Jevon Longdell, Physics Department, University of Otago, PO Box 56, Dunedin, 9054, Email: jevon.longdell@otago.ac.nz