Ultralow-threshold thin-film lithium niobate optical parametric oscillator

Journal Article · Mon Apr 12 00:00:00 EDT 2021 · Optica

DOI:https://doi.org/10.1364/OPTICA.418984· OSTI ID:1775190

Lu, Juanjuan ; Al Sayem, Ayed; Gong, Zheng ; Surya, Joshua B. ; Zou, Chang-Ling; Tang, Hong X.

Materials with strong second-order ( ${\mathrm{\chi \; <\#comment/>}}^{\left(2\right)}$ ) optical nonlinearity, especially lithium niobate, play a critical role in building optical parametric oscillators (OPOs). However, chip-scale integration of low-loss ${\mathrm{\chi \; <\#comment/>}}^{\left(2\right)}$ materials remains challenging and limits the threshold power of on-chip ${\mathrm{\chi \; <\#comment/>}}^{\left(2\right)}$ OPO. Here we report an on-chip lithium niobate optical parametric oscillator at the telecom wavelengths using a quasi-phase-matched, high-quality microring resonator, whose threshold power ( $\sim \; <\#comment/>30\text{µ <\#comment/>}\mathrm{W}$ ) is 400 times lower than that in previous ${\mathrm{\chi \; <\#comment/>}}^{\left(2\right)}$ integrated photonics platforms. An on-chip power conversion efficiency of 11% is obtained from pump to signal and idler fields at a pump power of 93 µW. The OPO wavelength tuning is achieved by varying the pump frequency and chip temperature. With the lowest power threshold among all on-chip OPOs demonstrated so far, as well as advantages including high conversion efficiency, flexibility in quasi-phase-matching, and device scalability, the thin-film lithium niobate OPO opens new opportunities for chip-based tunable classical and quantum light sources and provides a potential platform for realizing photonic neural networks.

• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0019406
• OSTI ID: 1775190
• Journal Information: Optica, Journal Name: Optica Vol. 8 Journal Issue: 4; ISSN 2334-2536
• Publisher: Optical Society of America
• Country of Publication: United States
• Language: English