UNSW Leaders in Science

Professor Michelle Simmons
Director, Australian Centre of Excellence for Quantum Computation and Communication Technology

Newton Building, Room W103
Phone: +61 2 9385 6313 - Email: michelle.simmons@unsw.edu.au

Career profilePublicationsResearch

Research

Atomic-scale Devices in Silicon and the Solid State Quantum Computer
Michelle is Director of the Australian Centre of Excellence for Quantum Computation and Communication Technology which houses unique combined scanning tunneling microscope (STM) and molecular beam epitaxy (MBE) systems dedicated to the fabrication of atomic-scale devices in silicon. She heads the group in atomic electronics in Sydney, whose ultimate aim is to fabricate the phosphorus in silicon qubit architecture one atomic layer at a time. Her team have achieved several major milestones: to incorporate a single phosphorus atom in the silicon surface with atomic precision; to develop a technique to make four terminal electrical contact to STM-patterned devices once they have been removed from the microscope environment and to correlate electrical device characteristics with dopant placement, putting them at the forefront of this field. Current research focuses on coherent charge transfer between single and coupled quantum dots with the goal of realizing prototype architectures for a solid state quantum computer.

In addition to the fabrication of quantum computer prototype devices a new program has been established to exploit the technology developed to build devices in silicon one atom at a time. This program will concentrate on developing atomic scale devices in silicon with applications appropriate to and beyond quantum computation, including atomic scale transistors, quantum wires and quantum circuits. Fundamental concepts of dopant ordering, device reproducibility and the key role that surface interface chemistry has on device operation will be addressed. Finally this program will expand to couple atomic scale lithography in silicon with molecular electronics.

Quantum Electronic Devices
In parallel her research interests are in the experimental investigation of quantum effects in extremely high quality semiconductor devices. As electronic devices have become smaller and purer, interaction effects between the individual charge carriers become significant and dominate the physics of these systems. Her research concentrates on understanding the fundamental nature of electrical conduction in high quality two-dimensional (2D) and one-dimensional (1D) GaAs-based electron and hole transistors. This work led to the classification of a new effect now known as the "0.7 structure" which remains the subject of intense investigation to understand the fundamental physics of one-dimensional systems.