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arXiv · 2402.04471

Reductive Quantum Phase Estimation

Nicholas J. C. Papadopoulos·Jarrod T. Reilly·John Drew Wilson·Murray J. Holland
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Abstract

Estimating a quantum phase is a necessary task in a wide range of fields of quantum science. To accomplish this task, two well-known methods have been developed in distinct contexts, namely, Ramsey interferometry (RI) in atomic and molecular physics and quantum phase estimation (QPE) in quantum computing. We demonstrate that these canonical examples are instances of a larger class of phase estimation protocols, which we call reductive quantum phase estimation (RQPE) circuits. Here we present an explicit algorithm that allows one to create an RQPE circuit. This circuit distinguishes an arbitrary set of phases with a fewer number of qubits and unitary applications, thereby solving a general class of quantum hypothesis testing to which RI and QPE belong. We further demonstrate a trade-off between measurement precision and phase distinguishability, which allows one to tune the circuit to be optimal for a specific application.

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Nicholas J. C. Papadopoulos, Jarrod T. Reilly, John Drew Wilson, Murray J. Holland. 2024-07-11. Reductive Quantum Phase Estimation. https://doi.org/10.1103/physrevresearch.6.033051

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