Dec 6, 2021
Hole spin qubits in elongated quantum dots
Date: December 6, 2021 |
2:30 pm –
Speaker: Monica Benito, Institute of Quantum Technologies of the German Aerospace Center (DLR) in Ulm / Germany
Location: Heinzel Seminar Room / Office Bldg West (I21.EG.101)
After summarizing the progress towards a scalable quantum computing architecture with Si QDs embedded in a micromagnet stray field [1,2], I will present recent results on hole spin qubits in Ge. By means of a novel analytical approach, we obtain an effective low-energy model for hole nanowires that accounts for orbital effects of the magnetic field exactly . We show the relevance of orbital effects on the SO interaction and, by complementing with numerical calculations, also on the g-factor. We predict optimal qubit operation at a charge noise sweetspot with Rabi frequencies in the GHz regime. Finally, by modeling planar QD hole spin qubits we find that they can present strong and tunable SO interaction if the confinement potential is properly squeezed. This confinement-induced SO interaction and therefore the qubit-resonator coupling could be turned on and off on demand in state-of-the-art qubits.
 X. Mi, M. Benito, S. Putz, D. M. Zajac, J. M. Taylor, G. Burkard, andJ. R. Petta, Nature 555, 599 (2018).
 M. Benito, J. R. Petta, and G. Burkard, Phys. Rev. B 100, 081412 (R)(2019).
 C. Adelsberger, M. Benito, S. Bosco, J. Klinovaja, and D. Loss,arXiv:2110.15039.
 S. Bosco, M. Benito, C. Adelsberger, and D. Loss, Phys. Rev. B 104,115425 (2021).