Professor Susan Coppersmith is a theoretical condensed matter physicist who has made substantial contributions to the understanding of a broad range of subjects, including glasses, biominerals, granular materials, and quantum computers. Her honors include fellowship in the Australian Academy of Science, the Australian Institute of Physics, and the Royal Society of New South Wales, as well as the American Physical Society, the American Association for the Advancement of Science, and the American Academy of Arts and Sciences, and membership in the National Academy of Sciences of the United States.
Professor Coppersmith is currently serving as Head of the School of Physics at UNSW Sydney. In the past she has served as Chair of the Condensed Matter and Materials Research Committee of the National Research Council of the US, as Chair of the Division of Condensed Matter Physics and of the Topical Group for Statistical and Nonlinear Physics of the American Physical Society, as Chair of the Section on Physics of the American Association for the Advancement of Science, and as Chair of the Board of Trustees of the Gordon Research Conferences.
Major current research activities include:
Quantum computing and high energy physics. Prof Coppersmith is a member of a collaboration with members at the University of Wisconsin-Madison, San Diego State University, and Tufts University that is working to use quantum computers to address fundamental problems in high energy physics. The two main thrusts are (1) to work to improve the discovery potential of direct dark matter experiments such as LZ by using quantum computation to calculate the properties of heavy target nuclei more accurately than is possible classically, and (2) to exploit quantum computers to study the relevance of entanglement to the behavior of neutrinos emitted in core-collapse supernova explosions, where the density of neutrinos is so high that neutrino-neutrino interactions are important and could play an important role in the explosion dynamics.
Designing nanostructures that support robust topologically nontrivial phases. Understanding how to manufacture nanostructures that can host topological electronic states could be transformative by for lowering the energy dissipation in electronics and by providing a means to implement quantum computation with topologically-protected states. Together with the experimental group of Prof Alexander Hamilton at UNSW and with the theoretical group of Dr Mark Friesen at the University of Wisconsin-Madison, Prof Coppersmith and her group are working to understand how to make robust topological phases using lithographically defined nanostructures with low levels of disorder. This project aims (1) to develop new lithographic designs based on the insights obtained from detailed electronic modeling and (2) to investigate how different types of disorder affect the stability of topologically nontrivial phases, and to use this knowledge to lithographic designs so that the deleterious effects of imperfections can be minimised.
Developing and optimising qubits in silicon/silicon-germanium heterostructures. In collaboration with groups at the University of Wisconsin-Madison and at Technical University Delft, Professor Coppersmith and her group have been working to develop quantum dot qubits hosted in silicon/silicon-germanium heterostructures. Her recent work includes a study that improves the understanding of the effects of strong electron-electron interactions in multiply occupied quantum dots and an investigation of how to increase the valley splitting in silicon/silicon-germanium heterostructures, which is the energy of the lowest-lying non-spin excited state in a quantum dot in this system. These investigations point to new routes for improving our ability to design quantum dots with properties that facilitate the operation of high-fidelity qubits.
Selected recent publications:
Michael J. Cervia, Pooja Siwach, Amol V. Patwardhan, A. B. Balantekin, S. N. Coppersmith, and Calvin W. Johnson, “Collective neutrino oscillations with tensor networks using a time-dependent variational principle,” preprint arXiv:2202.01865, Physical Review D 105, 123025 (2022). DOI: 10.1103/PhysRevD.105.123025
H. Ekmel Ercan, Mark Friesen, and S. N. Coppersmith, “Charge-noise resilience of two-electron quantum dots in Si/SiGe heterostructures,” preprint arXiv:2105.10643, Physical Review Letters. 128, 247701 (2022). DOI: 10.1103/PhysRevLett.128.247701
J. P. Dodson, H. Ekmel Ercan, J. Corrigan, Merritt Losert, Nathan Holman, Thomas McJunkin, L. F. Edge, Mark Friesen, S. N. Coppersmith, and M. A. Eriksson, “How valley-orbit states in silicon quantum dots probe quantum well interfaces,” preprint arXiv:2103.14702, Physical Review Letters 128, 146802 (2022). DOI: 10.1103/PhysRevLett.128
J. Corrigan, J. P. Dodson, H. Ekmel Ercan, J. C. Abadillo-Uriel, Brandur Thorgrimsson, T. J. Knapp, Nathan Holman, Thomas McJunkin, Samuel F. Neyens, E. R. MacQuarrie, Ryan H. Foote, L. F. Edge, Mark Friesen, S. N. Coppersmith, M. A. Eriksson, “Coherent control and spectroscopy of a semiconductor quantum dot Wigner molecule,” preprint arXiv:2009.13572, Physical Review Letters 127, 127701 (2021). DOI: 10.1103/PhysRevLett.127.127701