Phase estimation algorithm for the multibeam optical metrology

Abstract

Unitary fourier transform lies at the core of the multitudinous computational and metrological algorithms. Here we show experimentally how the unitary fourier transform-based phase estimation protocol, used namely in quantum metrology, can be translated into the classical linear optical framework. the developed setup made of beam splitters, mirrors and phase shifters demonstrates how the classical coherence, similarly to the quantum coherence, poses a resource for obtaining information about the measurable physical quantities. our study opens route to the reliable implementation of the small-scale unitary algorithms on path-encoded qudits, thus establishing an easily accessible platform for unitary computation.

Optimized emulation of quantum magnetometry via superconducting qubits

“…In our approach we do not adopt any similar techniques, though it has recently been shown that such schemes should be considered for dc sensing as well [68,69]. Utilization of multilevel artificial atoms theoretically allows for better sensitivity [33,34,70], but coherence of higher transmon levels may be an issue in such strategies.…”

Linear Ascending Metrological Algorithm

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