Hole spin manipulation in inhomogeneous and non-separable electric fields

Abstract

The usual models for electrical spin manipulation in semiconductor quantum dots assume that the confinement potential is separable in the three spatial dimensions and that the AC drive field is homogeneous. However, the electric field induced by the gates in quantum dot devices is not fully separable and displays significant inhomogeneities. Here, we address the electrical manipulation of hole spins in semiconductor heterostructures subject to inhomogeneous vertical electric fields and/or in-plane AC electric fields. We consider Ge quantum dots electrically confined in a Ge/GeSi quantum well as an illustration. We show that the lack of separability between the vertical and in-plane motions gives rise to an additional spin-orbit coupling mechanism (beyond the usual linear and cubic in momentum Rashba terms) that modulates the principal axes of the hole gyromagnetic g-matrix. This non-separability mechanism can be of the same order of magnitude as Rashba-type interactions, and enables spin manipulation when the magnetic field is applied in the plane of the heterostructure even if the dot is symmetric (disk-shaped). More generally, we show that Rabi oscillations in strongly patterned electric fields harness a variety of g-factor modulations. We discuss the implications for the design, modeling and understanding of hole spin qubit devices.

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• A four-qubit germanium quantum processor
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• Spin decoherence of a heavy hole coupled to nuclear spins in a quantum dot
• A hole spin qubit in a fin field-effect transistor above 4 kelvin
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• Simple model for electrical hole spin manipulation in semiconductor quantum dots: Impact of dot material and orientation
• Fully tunable longitudinal spin-photon interactions in Si and Ge quantum dots
• Lightly-strained germanium quantum wells with hole mobility exceeding one million
• Variability of electron and hole spin qubits due to interface roughness and charge traps
• Longitudinal and transverse electric field manipulation of hole spin-orbit qubits in one-dimensional channels
• Emergence of the strong tunable linear Rashba spin-orbit coupling of two-dimensional hole gases in semiconductor quantum
• The emergent linear Rashba spin-orbit coupling offering the fast manipulation of hole-spin qubits in germanium

Cited by in corpus (24)

• Operating semiconductor quantum processors with hopping spins
• Sweet-spot operation of a germanium hole spin qubit with highly anisotropic noise sensitivity
• Hole spin driving by strain-induced spin-orbit interactions
• Electrical operation of planar Ge hole spin qubits in an in-plane magnetic field
• Impact of interface traps on charge noise, mobility and percolation density in Ge/SiGe heterostructures
• Linear-in-momentum spin orbit interactions in planar Ge/GeSi heterostructures and spin qubits
• High-fidelity spin qubit shuttling via large spin-orbit interaction
• Bichromatic Rabi Control of Semiconductor Qubits
• Geometry of the dephasing sweet spots of spin-orbit qubits
• Electrical operation of hole spin qubits in planar MOS silicon quantum dots
• Single-step high-fidelity three-qubit gates by anisotropic chiral interactions
• Dephasing of planar Ge hole spin qubits due to 1/$\text{f}$ charge noise
• Modelling of planar germanium hole qubits in electric and magnetic fields
• Protocols to measure the non-Abelian Berry phase by pumping a spin qubit through a quantum-dot loop
• A spinless spin qubit
• Theory of superconducting proximity effect in hole-based hybrid semiconductor-superconductor devices
• Variability of hole spin qubits in planar Germanium
• Hole spin splitting in a Ge quantum dot with finite barriers
• Cancelling second order frequency shifts in Ge hole spin qubits via bichromatic control
• Photodriven germanium hole qubit
• Dressed basis sets for the modeling of exchange interactions in double quantum dots
• Role of anisotropic confining potential and elliptical driving in dynamics of a Ge hole qubit
• Switchable spin-photon coupling with hole spins in single-quantum dots
• Sweet-spot protection of hole spins in sparse arrays via spin-dependent magnetotunneling