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arXiv · 1404.0274

Reconfigurable on-chip entangled sources based on lithium-niobate waveguide circuits

H. Jin·F. M. Liu·P. Xu·J. L. Xia·M. L. Zhong·Y. Yuan·Y. X. Gong·W. Wang·S. N. Zhu
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Abstract

Integrated quantum optics becomes a consequent tendency towards practical quantum information processing. Here, we report the on-chip generation and manipulation of photonic entanglement based on reconfigurable lithium niobate waveguide circuits. By introducing periodically poled structure into the waveguide interferometer, two individual photon-pair sources with controllable phase-shift are produced and cascaded by a quantum interference, resulting in a deterministically separated identical photon pair. The state is characterized by 92.9% visibility Hong-Ou-Mandel interference. Continuous morphing from two-photon separated state to bunched state is further demonstrated by on-chip control of electro-optic phase-shift. The photon flux reaches ~1.4*10^7 pairs nm-1 mW-1. Our work presents a scenario for on-chip engineering of different photon sources and paves a way to the fully integrated quantum technologies.

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H. Jin, F. M. Liu, P. Xu, J. L. Xia, M. L. Zhong, Y. Yuan, Y. X. Gong, W. Wang, S. N. Zhu. 2014-04-01. Reconfigurable on-chip entangled sources based on lithium-niobate waveguide circuits. https://arxiv.org/abs/1404.0274

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