Efficient generation of broadband photon pairs in shallow-etched lithium niobate nanowaveguide

Abstract

We design and fabricate shallow-etched periodically poled lithium niobate waveguide to realize highly-efficient broadband spontaneous parametric down-conversion~(SPDC) on nanophotonic chip. The shallow-etched waveguide is capable to tolerate the non-uniformities of waveguide width induced by fabrication imperfections, enabling generation of photon pairs with high count rate and bandwidth. We demonstrate photon-pair generation with a high brightness of 11.7~GHz/mW and bandwidth of 22~THz, in a 5.7-mm-long PPLN waveguide. The generated photon pairs exhibit strong temporal correlation with a coincidence-to-accidental ratio up to 16262$\pm$850. Our results confirm the feasibility of shallow etching in fabrication of efficient SPDC device on platform of lithium niobate on insulator, and benefit quantum information processing with broadband photon source.

References in corpus (2)

• Optical Quantum Computing
• Spectrally separable photon-pair generation in dispersion engineered thin-film lithium niobate

Cited by in corpus (3)

• High-efficiency On-chip Quantum Photon Source in Modal Phase-matched Lithium Niobate Nanowaveguide
• Ultrabroadband tunable difference frequency generation in standardized thin-film lithium niobate platform
• Advancing the heralded photon-number-state characterization by understanding the interplay of experimental settings