Roy Arkadev, Ledezma Luis, Costa Luis, Gray Robert, Sekine Ryoto, Guo Qiushi, Liu Mingchen, Briggs Ryan M, Marandi Alireza
Department of Electrical Engineering, California Institute of Technology, Pasadena, California, 91125, USA.
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, 91109, USA.
Nat Commun. 2023 Oct 17;14(1):6549. doi: 10.1038/s41467-023-42289-0.
Optical frequency comb is an enabling technology for a multitude of applications from metrology to ranging and communications. The tremendous progress in sources of optical frequency combs has mostly been centered around the near-infrared spectral region, while many applications demand sources in the visible and mid-infrared, which have so far been challenging to achieve, especially in nanophotonics. Here, we report widely tunable frequency comb generation using optical parametric oscillators in lithium niobate nanophotonics. We demonstrate sub-picosecond frequency combs tunable beyond an octave extending from 1.5 up to 3.3 μm with femtojoule-level thresholds on a single chip. We utilize the up-conversion of the infrared combs to generate visible frequency combs reaching 620 nm on the same chip. The ultra-broadband tunability and visible-to-mid-infrared spectral coverage of our source highlight a practical and universal path for the realization of efficient frequency comb sources in nanophotonics, overcoming their spectral sparsity.
光学频率梳是一种使能技术，可用于从计量学到测距和通信等众多应用。光学频率梳源的巨大进展大多集中在近红外光谱区域，而许多应用需要可见光和中红外波段的光源，到目前为止，实现这些光源具有挑战性，尤其是在纳米光子学领域。在此，我们报告了利用铌酸锂纳米光子学中的光学参量振荡器产生宽可调谐频率梳。我们展示了亚皮秒频率梳在单芯片上可在超过一个倍频程范围内调谐，范围从1.5μm扩展到3.3μm，且阈值为飞焦量级。我们利用红外梳的上转换在同一芯片上产生了可达620nm的可见频率梳。我们光源的超宽带可调谐性以及从可见光到中红外的光谱覆盖，突出了在纳米光子学中实现高效频率梳源的一条实用且通用的途径，克服了其光谱稀疏性问题。
