Fluxonium superconducting qubit's fast control methods enable record-setting 99.998% single-qubit gate fidelity

https://phys.org/news/2025-01-fast-methods-enable-fidelity-superconducting.html

"enables sustained computation through quantum error correction... fast gates reduce impact of decoherence, but can introduce counter-rotating dynamics error because of way qubits are controlled using electromagnetic waves... overcome with low-frequency qubits such as fluxonium, by controlling the relative phase of charge and flux drives of the superconducting qubit... circularly polarized drives immune to counter-rotating errors"