Robust micro-magnet design for fast electrical manipulations of single spins in quantum dots

摘要

Tailoring spin coupling to electric fields is central to spintronics andspin-based quantum information processing. We present an optimal micromagnetdesign that produces appropriate stray magnetic fields to mediate fastelectrical spin manipulations in nanodevices. We quantify the practicalrequirements for spatial field inhomogeneity and tolerance for misalignmentwith spins, and propose a design scheme to improve the spin-rotation frequency(to exceed 50MHz in GaAs nanostructures). We then validate our design byexperiments in separate devices. Our results will open a route to rapidlycontrol solid-state electron spins with limited lifetimes and to study coherentspin dynamics in solids.