Quantum information science is barely ten years old yet already it is forcing new directions in nanotechnlogy and changing the way we understand the physical world.
Physics places constraints on how we can act in the world; for example, the laws of thermodynamics rule out perpetual motion machines.
Our current best theoretical description of the physical world is quantum mechanics and not surprisingly quantum physics places new constraints on what we can do.
More surprising however is the dawning realisation that quantum physics can enable tasks not possible in the everyday world of classical physics, the physics of Newton, Faraday etc.
In the last decade this has led to the beginnings of a new science, quantum information science.
Quantum information science
The goal of this new science is to determine how information can be processed and communicated if we harness the principles of quantum physics.
Quantum teleportation and quantum computation are two of the most exciting discoveries of this new field
The University of Queensland has a growing research effort making an international impact in this burgeoning new science.
The UQ effort in quantum information science is currently spread over two groups in the School of Physical Sciences: the Australian Research Council’s Centre for Quantum Computer Technology (CQCT), and the Quantum Information Theory Group led by Associate Professor Michael Nielsen.
The CQCT is a very large research program set up with the aim of determining if we can build a quantum device that can compute exponentially more efficiently than a conventional computer.
The suggestion that this is possible goes back more than a decade, but only recently has a worldwide experimental effort developed to put these ideas into practice. At this stage no one expects to be able to build a full quantum computer with existing technologies.
The most anyone can hope for is to construct a few simple quantum switches that would form the building blocks of a future technology.
The UQ node of the SRC is focusing on optical methods to realise a quantum computer.
US collaboration
In 2001, members of the UQ node of CQCT, together with researchers at Los Alamos National Laboratory in the US, discovered a completely new way to harness optics in the service of quantum information processing.
The idea was first presented in the prestigious scientific journal Nature in January 2001. Subsequently, the UQ node was awarded a $1.5 million grant from the US government to develop a laboratory to put the theory into practice.
This program is led by Drs Tim Ralph and Andrew White in the Physics Department. The new laboratory became operational at the end of 2001 and is now well on its way to demonstrating the first optical quantum logical element.
As a result of the US funding, UQ researchers joined a select group of people worldwide funded by the US Government with the aim of determining the best technological path to a quantum computer.
Last month, three UQ researchers and four from the University of New South Wales (also members of CQCT) travelled to Nashville to attend the US Government’s Quantum Computing Program Review, an invitation-only meeting of the world’s key researchers in the field.
The Australian team presented two talks as well as seven posters at this meeting and the work was generally regarded as among the highlights of the week-long gathering.
The Quantum Information Theory Group
In addition to the CQCT, the School of Physical Science hosts the Quantum Information Theory Group.
This is a multi-disciplinary group of researchers involving the Departments of Mathematics and Physics and led by Associate Professor Michael Nielsen. The group has a much broader brief than the CQCT.
Their goal is to help lay the foundations for a future quantum information science. Recently the group received support from the University to take their effort to a new stage and recruit new skills from mathematics and computer science.
UQ is a significant world centre in the field and will only become more so over the next five years. Having such a powerful research effort in a teaching institution will enable UQ to play a key role in training Australia’s future quantum information scientists and help drive the nation forward into this new scientific endeavour.
