Multi-Wavelength Quantum Light Sources on Silicon Nitride Micro-Ring Chip

Multi-wavelength quantum light sources are extremely desired in establishing communication links among multiple users for realizing quantum networks. Despite recent impressive advances, developing such a quantum light source with high quality remains challenging. Here a multi-wavelength quantum light source using a silicon nitride micro-ring with a free spectral range of 200 GHz is demonstrated. The generation of eight-wavelength-paired photon pairs is ensured in a wavelength range of 25.6 nm. With device optimization and noise-rejecting filters, this source enables the generation of heralded single-photons at a rate of 62 kHz with gh(2)(0)=0.014 & PLUSMN;0.001$g<^>{(2)}_{\text{h}}(0)=0.014\pm 0.001$ and the generation of energy-time entangled photons with a visibility of 99.39 & PLUSMN;0.45%$99.39\pm 0.45\%$ in the Franson interferometer. These results, at room temperature and telecom wavelength, in a CMOS-compatible platform, represent an important step toward integrated quantum photonic devices, which pave the way for realizing a large-scale quantum network. A multi-wavelength quantum light source with a silicon nitride micro-ring resonator in a wavelength range of 25.6 nm at telecom band is demonstrated. The source enables the generation of heralded single photons at a rate of 62 kHz with gh(2)(0)=0.014 & PLUSMN;0.001$g<^>{(2)}_{h}(0)=0.014\pm 0.001$ and energy-time entangled photon pairs with a typical two-photon interference visibility of 99.39 & PLUSMN;0.45%$99.39\pm 0.45\%$. image

Automated summary

This study demonstrates a multi-wavelength quantum light source using a silicon nitride micro-ring with a free spectral range of 200 GHz. By optimizing the device and using noise-rejecting filters, the source can generate eight-wavelength-paired photon pairs in a wavelength range of 25.6 nm. It also enables the generation of heralded single-photons at a rate of 62 kHz with gh(2)(0)=0.014 & PLUSMN;0.001$g<^>{(2)}_{h}(0)=0.014\pm 0.001$ and energy-time entangled photons with a visibility of 99.39 & PLUSMN;0.45%$99.39\pm 0.45\%$ in the Franson interferometer. These results, achieved at room temperature and telecom wavelength, on a CMOS-compatible platform, represent a significant step towards integrated quantum photonic devices and the realization of large-scale quantum networks.