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Physical Review A

Photon-number entanglement from cascaded parametric down-conversion

Shu-Tian Xue, He Jiang, Jing Wang, Zhi-Cheng Ren, Xi-Lin Wang, Hui-Tian Wang

Published Dec 1, 2025• 0 citations
Publisher

Abstract

We propose a protocol for generating photon-number entanglement through sequential parametric down-conversion processes. This protocol is fully compatible with linear optics experiments and can be easily implemented as an extension of the path-identity scheme. We present a detailed scheme for the creation of heralded two-mode photon-number high-dimensional entanglement with the form of $|00\ensuremath{\rangle}+|11\ensuremath{\rangle}+|22\ensuremath{\rangle}$. In addition, the protocol enables us to easily generate various photon-number-entangled states, which have potential applications in quantum communication, quantum precision measurements, and continuous-variable quantum information.

DOI
10.1103/slsq-t87h

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