Daniel Loss

Academic Affiliation: University of Basel

Title: Hole spin qubits for quantum computing in Si and Ge quantum dots

Abstract: 

Hole spin qubits are frontrunner platforms for scalable quantum computers in Si and Ge semiconductors because of their large spin-orbit interaction which enables ultrafast all-electric qubit control at low power. The fastest spin qubits to date are defined in long quantum dots with two tight confinement directions, when the driving field is aligned to the smooth direction [1]. However, in these systems the lifetime of the qubit is strongly limited by charge noise, a major issue in hole qubits. I will give an overview of recent theoretical and experimental results [1-5] that have led to a series of testable predictions such as sweet spots for devices in Si and Ge semiconductors currently implemented in the Swiss National Center on Spin Qubits led by the University of Basel and IBM Zurich.

References

[1] Ultrafast Hole Spin Qubit with Gate-Tunable Spin-Orbit Switch. F. N. M. Froning, L. C. Camenzind, O. A. H. van der Molen, A. Li, E. P. A. M. Bakkers, D. M. Zumbühl, F. R. Braakman; Nature Nanotechnology 16 (2021).

[2] Fully tunable hyperfine interactions of hole spin qubits in Si and Ge quantum dots.
S. Bosco and D.Loss, Phys. Rev. Lett. 127, 190501 (2021).

[3] Hole spin qubits in Si FinFETs with fully tunable spin-orbit coupling and sweet spots for charge noise. S. Bosco, B. Hetényi, and D.Loss; PRX Quantum 2, 010348 (2021).

[4] The germanium quantum information route. G. Scappucci, C. Kloeffel, F. A. Zwanenburg, D. Loss, M. Myronov, J.-J. Zhang, S. De Franceschi, G. Katsaros, and M. Veldhorst; Nat Rev Mater (2020).

[5] A hole spin qubit in a fin field-effect transistor above 4 Kelvin. L. C. Camenzind, S. Geyer, A. Fuhrer, R. J. Warburton, D. M. Zumbühl, A. V. Kuhlmann; Nature Electronics 2022.