arXiv:2501.01088 · Quantum Science and Technology

Detecting high-dimensional entanglement by randomized product projections

Jin‐Min Liang, Shuheng Liu, Shao-Ming Fei, Qiongyi He

Published Jan 21, 2026• 1 citation

Abstract

Abstract The characterization of high-dimensional entanglement plays a crucial role in the field of quantum information science. Conventional entanglement criteria measuring coherent superpositions of multiple basis states face experimental bottlenecks on most physical platforms due to limited multi-channel control. Here, we introduce a practically efficient detection strategy based on randomized product projections. We show that the first-order moments of such projections can be used to estimate entanglement fidelity, thereby enabling practical and efficient certification of the Schmidt number (SN) in high-dimensional bipartite systems. By constructing optimal observables, it is sufficient to merely measure a single basis state, substantially reducing experimental overhead. Moreover, we present an algorithm to obtain a lower bound of the SN with a high confidence level from a limited number of experimental data. Our results open up resource-efficient experimental avenues to detect high-dimensional entanglement and test its implementations in modern information technologies.

DOI: 10.1088/2058-9565/ae3b6e

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