Optimising silicon/silicon-germanium quantum dot qubits (45' + 15')

• Susan Coppersmith (UNSW Sydney)

**Abstract**: Silicon/silicon-germanium (Si/SiGe) quantum well heterostructures comprise a leading materials system for hosting semiconducting quantum dot qubits. Compared to the silicon metal-oxide-semiconductor materials stack used in most current classical computers, Si/SiGe has the advantage that the qubits are confined near a high-quality epitaxial interface that is relatively far from defects that can degrade performance. This talk will present our recent theoretical work that demonstrates that qubits in Si/SiGe heterostructures are affected strongly by compositional disorder in the SiGe, and discusses how this understanding can be exploited to optimise quantum dot qubits in Si/SiGe. **Short bio**: Susan Coppersmith is a theoretical physicist in the School of Physics at UNSW Sydney whose research focus over the past decade is on the development of nanodevices with novel and useful properties that are robust to imperfections and disorder. Her work has had substantial impact on the development of quantum dot qubits in a silicon platform similar to that used for current classical electronic devices. Her work also focuses on the development of novel electronic devices that exploit electronic phases with nontrivial topology to enhance quantum coherence. Her scientific contributions have been recognised by the New South Wales Premier’s Prize for Excellence in Mathematics, Earth Sciences, Chemistry or Physics, by election to Fellowship in the Australian Academy of Science, and to Membership in the National Academy of Sciences in the USA.