Spin-orbit enhancement in Si/SiGe heterostructures with oscillating Ge concentration

Abstract

Electrons in Si/SiGe quantum dots are a promising platform for quantum computation. Many leading designs, however, rely on synthetic spin-orbit coupling arising from micromagnets, leading to challenges in scaling. Here, it is shown that the intrinsic spin-orbit coupling of the conduction-band valleys can be enhanced by over an order of magnitude by including Ge concentration oscillations of an appropriate wavelength within the quantum-well region. This enables fast spin manipulation using electric dipole spin resonance in the absence of micromagnets.