We propose a minimal design modification of Ge planar quantum dot devices that enhances the spin-orbit interaction by orders of magnitude and enables low power ultrafast hole-spin qubit operations.
Hole spin qubits in planar Ge heterostructures are one of the frontrunner platforms for scalable quantum computers. In these systems, the spin-orbit interactions permit efficient all-electric qubit control. We propose a minimal design modification of planar devices that enhances these interactions by orders of magnitude and enables low power ultrafast qubit operations in the GHz range. Our approach is based on an asymmetric potential that strongly squeezes the quantum dot in one direction. This connement-induced spin-orbit interaction does not rely on microscopic details of the device such as growth direction or strain, and could be turned on and o on demand in state-of-the-art qubits.
Preprint on arXiv: