Certifying Quantum States with Uniform Measurements

TL;DR

This paper explores the use of uniform measurements, which are resource-efficient and parallelizable, to certify and characterize quantum states, specifically graph states, in quantum information processing.

Contribution

It introduces a certification algorithm using uniform measurements for graph states and demonstrates an experimental scheme with Rydberg atom arrays.

Findings

Uniform measurements can certify graph states efficiently.

The proposed algorithm has a proven performance guarantee.

Experimental scheme based on Rydberg atoms is feasible.

Abstract

Qubit-resolved operations and measurements are required for most current quantum information processing schemes. However, these operations can be experimentally costly due to the need for local addressing, demanding significant classical control. A more resource-efficient alternative to extract information is uniform measurement, where a site-independent rotation of qubits is performed before measuring in the computational basis. This operation can be performed in parallel, or globally, in atom- and ion-based platforms, reducing resource cost and increasing fidelity. In this work, we initiate the exploration of the utility of this operation in quantum information processing. In particular, we demonstrate that uniform measurements can certify certain graph states, a family of highly entangled and broadly useful quantum states. We provide a sample-efficient certification algorithm with a proved performance guarantee, together with an experimental scheme based on analog-mode Rydberg atom arrays. Uniform measurements, therefore, allow direct and efficient characterization of quantum states on quantum platforms in a hitherto unexplored manner.