Proximal quantum control of spin qubits with highly localized control field from magnetic skyrmions

Implementing high-fidelity quantum gates, requires highly localized control fields to act on the desired spin qubit while minimizing gate errors and cross-talk in neighboring qubits. Generating a localized RF magnetic field presents a significant challenge due to the absence of elementary magnetic monopoles. We propose a technique that employs a combination of divergent and convergent magnetic skyrmions to produce a control field capable of manipulating spin qubits with high fidelity. We chose to use 2D skyrmions because they are similar to 3D hedgehog structures, which act like magnetic monopoles and easier to work with in standard semiconductor processes. We compared the spin evolution and gate fidelities of spin qubits in scenarios involving proximal skyrmions and proximal nanomagnets [1]. Our simulations indicate the potential for achieving gate fidelities above 99.9% for single-qubit gates and gate operation times exceeding 1000 times the decoherence time of the spin qubits [2]. Furthermore, the skyrmion configuration produces significantly lower field in neighboring spin qubits, making it more suitable for scalable quantum control architecture than the proximal nanomagnets.

1.Niknam, M, et al. Comm Phy 5, 284 no. 1 (2022).

2.Gottesman, D Phys. Rev. A 57, 127–137 (1998).