Hybrid Epitaxial Materials at the Heart of the Quantum Computing Revolution

This talk will highlight several approaches to quantum information made possible by revolutionary new capabilities in materials growth. Controlled epitaxial growth of semiconductors, superconductors, and ferromagnets can create hybrid materials with properties not available in a single material, which are useful for creating topological and conventional qubits. This ranges from topological superconductors exhibiting signatures of Majorana zero modes [1], including at zero applied magnetic field [2] to voltage-controlled transmon-like Josephson qubits [3]. Along the way, much basic physics remains to be uncovered and understood, shedding light on topological materials, anomalous metals, even the lowly quantum point contact presents new aspects in these hybrid systems. A variety of basic and applied results are surveyed. Research supported by Microsoft and the Danish National Research Foundation.

[1] R. M. Lutchyn, E. P. A. M. Bakkers, L. P. Kouwenhoven, P. Krogstrup, C. M. Marcus, and Y. Oreg, Nature Reviews Materials 3, 1 (2018).
[2] S. Vaitiekenas, Y. Liu, P. Krogstrup, and C. M. Marcus, Nat Phys 464, 1 (2020).
[3] T. W. Larsen, M. E. Gershenson, L. Casparis, A. Kringhøj, N. J. Pearson, R. P. G. McNeil, F. Kuemmeth, P. Krogstrup, K. D. Petersson, and C. M. Marcus, Phys Rev Lett 125, 056801 (2020).