Robust and Parallel Control of Many Qubits

Abstract:The rapid growth in size of quantum devices demands efficient ways to control them, which is challenging for systems with thousands of qubits or more. Here, we present a simple yet powerful solution: robust, site-dependent control of an arbitrary number of qubits in parallel with only minimal local tunability of the driving field. Inspired by recent experimental advances, we consider access to only one of three constrained local control capabilities: local control of either the phase or amplitude of the beam at each qubit, or individual $Z$ rotations. In each case, we devise parallelizable composite pulse sequences to realize arbitrary single-qubit unitaries robust against quasistatic amplitude and frequency fluctuations. Numerical demonstration shows that our approach outperforms existing sequences such as BB1 and CORPSE in almost all regimes considered, achieving average fidelity~$>0.999$ under a decoherence rate of~$\sim 10^{-5}$, even with a few percent amplitude and frequency error. Our results indicate that even for very large qubit ensembles, accurate, individual manipulation can be achieved despite substantial control inhomogeneity.

arXiv:2312.08426 [quant-ph]

(or arXiv:2312.08426v2 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2312.08426 Focus to learn more arXiv-issued DOI via DataCite

Phys. Rev. Research 8, L032043 (2026)

https://doi.org/10.1103/n2hz-8zy2 Focus to learn more DOI(s) linking to related resources

arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website.

Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them.

Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs.