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Chinese Physics Letters

Ultra-Compact Transverse Mode Quantum Interference Device on Silicon

Yang Li, Yujie Cheng, Shumin Jiang, Peipeng Xu, Junjie Du, Yingxuan Zhao, Zhen Sheng, Tianzhu Zhang, Hao Li, Lixing You, Guang‐Can Guo, Lan‐Tian Feng, Xi‐Feng Ren, Fuwan Gan

Published Sep 25, 2025• 0 citations
Publisher

Abstract

Abstract Quantum photonic integrated circuits offer enhanced stability and scalability for quantum communications, sensing, and computing. Transverse modes in multimode waveguides enable high-dimensional scalability and versatile photon manipulation, but practical adoption requires compact and fabrication-tolerant quantum interference devices. Here, we present an ultra-compact taper-stepped beamsplitter that enables quantum interference between photon pairs in different transverse modes, and cascade it to realize NOON state interferometry. We experimentally achieve high visibilities of 93.9% for HOM interference and 86.5% for NOON state interference, demonstrating that efficient mode interference with active tuning can be realized on this platform.

DOI
10.1088/0256-307x/42/11/110603

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