Ultra-low-power second-order nonlinear optics on a chip.
2022; 13 (1): 4532
Second-order nonlinear optical processes convert light from one wavelength to another and generate quantum entanglement. Creating chip-scale devices to efficiently control these interactions greatly increases the reach of photonics. Existing silicon-based photonic circuits utilize the third-order optical nonlinearity, but an analogous integrated platform for second-order nonlinear optics remains an outstanding challenge. Here we demonstrate efficient frequency doubling and parametric oscillation with a threshold of tens of micro-watts in an integrated thin-film lithium niobate photonic circuit. We achieve degenerate and non-degenerate operation of the parametric oscillator at room temperature and tune its emission over one terahertz by varying the pump frequency by hundreds of megahertz. Finally, we observe cascaded second-order processes that result in parametric oscillation. These resonant second-order nonlinear circuits will form a crucial part of the emerging nonlinear and quantum photonics platforms.
View details for DOI 10.1038/s41467-022-31134-5
View details for PubMedID 35927246
Spectrally separable photon-pair generation in dispersion engineered thin-film lithium niobate
2022; 47 (11): 2830-2833
Existing nonlinear-optic implementations of pure, unfiltered heralded single-photon sources do not offer the scalability required for densely integrated quantum networks. Additionally, lithium niobate has hitherto been unsuitable for such use due to its material dispersion. We engineer the dispersion and the quasi-phasematching conditions of a waveguide in the rapidly emerging thin-film lithium niobate platform to generate spectrally separable photon pairs in the telecommunications band. Such photon pairs can be used as spectrally pure heralded single-photon sources in quantum networks. We estimate a heralded-state spectral purity of >94% based on joint spectral intensity measurements. Further, a joint spectral phase-sensitive measurement of the unheralded time-integrated second-order correlation function yields a heralded-state purity of (86±5)%.
View details for DOI 10.1364/OL.456873
View details for Web of Science ID 000807404900056
View details for PubMedID 35648941
- Dispersion-engineered chi((2)) nanophotonics: a flexible tool for nonclassical light JOURNAL OF PHYSICS-PHOTONICS 2021; 3 (4)
- Mid-infrared nonlinear optics in thin-film lithium niobate on sapphire OPTICA 2021; 8 (6): 921-924
Fully-Resonant Second Harmonic Generation in Periodically Poled Thin-Film Lithium Niobate
View details for Web of Science ID 000831479801219
Optical Parametric Oscillator in Thin-Film Lithium Niobate with a 130 mu W Threshold
View details for Web of Science ID 000831479803278
Mid-infrared nonlinear optics in thin-film lithium niobate on sapphire
View details for Web of Science ID 000831479802196