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arXiv · 1703.03538

Spin-orbit dynamics of single acceptor atoms in silicon

J. van der Heijden·T. Kobayashi·M. G. House·J. Salfi·S. Barraud·R. Lavieville·M. Y. Simmons·S. Rogge
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Abstract

Two-level quantum systems with strong spin-orbit coupling allow for all-electrical qubit control and long-distance qubit coupling via microwave and phonon cavities, making them of particular interest for scalable quantum information technologies. In silicon, a strong spin-orbit coupling exists within the spin-3/2 system of acceptor atoms and their energy levels and properties are expected to be highly tunable. Here we show the influence of local symmetry tuning on the acceptor spin-dynamics, measured in the single-atom regime. Spin-selective tunneling between two coupled boron atoms in a commercial CMOS transistor is utilised for spin-readout, which allows for the probing of the two-hole spin relaxation mechanisms. A relaxation-hotspot is measured and explained by the mixing of acceptor heavy and light hole states. Furthermore, excited state spectroscopy indicates a magnetic field controlled rotation of the quantization axes of the atoms. These observations demonstrate the tunability of the spin-orbit states and dynamics of this spin-3/2 system.

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J. van der Heijden, T. Kobayashi, M. G. House, J. Salfi, S. Barraud, R. Lavieville, M. Y. Simmons, S. Rogge. 2017-03-10. Spin-orbit dynamics of single acceptor atoms in silicon. https://doi.org/10.1126/sciadv.aat9199

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