npj Quantum Information, Published online: 26 October 2024; doi:10.1038/s41534-024-00904-y
Robust projective measurements through measuring code-inspired observables
Quantum measurements are ubiquitous in quantum information processing tasks, but errors can render their outputs unreliable.
Here, researchers present a scheme that implements a robust projective measurement through measuring code-inspired observables. Namely, given a projective POVM, a classical code, and a constraint on the number of measurement outcomes each observable can have, they have constructed commuting observables whose measurement is equivalent to the projective measurement in the noiseless setting.
Moreover, they can correct terrors on the classical outcomes of the observables’ measurement if the classical code corrects t errors. Since their scheme does not require the encoding of quantum data onto a quantum error correction code, it can help construct robust measurements for near-term quantum algorithms that do not use quantum error correction. Moreover, their scheme works for any projective POVM, and hence can allow robust syndrome extraction procedures in non-stabilizer quantum error correction codes.