Integrated frequency comb generator for clock and carrier dissemination

光学频率梳(OFC)彻底改变了计时、光谱学和计量学[1]。十年前发现的OFC可以在光学微谐振器中产生，在那里形成明亮的耗散克尔孤子。这些类型的OFC被称为“孤子微梳”[2]，并且已经在系统级应用中使用。与此同时，用于产生微梳的光子集成平台也取得了实质性的进展，其中III-V集成锁模激光器和Si3N4基克尔梳子[3]已经成为很有前途的平台。然而，当使用连续波(CW)泵浦时，种子信号到梳状音调的转换效率很低。这导致了低功率、低光信噪比的梳状色调，阻碍了克尔梳状结构在光通信、微波光子学和光电子仪器等领域的应用。在这里，我们的目标是通过结合集成III-V锁模激光器[4]和克尔微梳来克服这些限制，其中集成III-V锁模激光器输出短光脉冲来泵浦克尔微梳。与现有方法相比，我们提出的方法可以显著降低泵浦阈值，提高转换效率，从而为电信和射频应用提供集成、高性能和高能效的频率梳。

Optical frequency combs (OFCs) have revolutionized timing, spectroscopy and metrology [1]. Discovered a decade ago, OFCs can be generated in optical micro- resonators where bright dissipative Kerr solitons are formed. These types of OFCs are referred to as "soliton microcombs" [2] and have already been used in system-level applications. In parallel, there has been substantial progress in photonic integrated platforms for microcomb generation, among which III-V integrated mode locked laser and Si3N4 based Kerr comb [3] has emerged as promising platforms. Nevertheless, the conversion efficiency from the seed signal to comb tones are low when using continuous wave (CW) pumping. This results in low power and low optical signal to noise ratio (OSNR) comb tones, which has impeded the application of Kerr comb in the fields of optical communications, microwave photonics and optoelectronic instruments. Here, we aim to overcome these limitations by combining integrated III-V mode-locked lasers [4] and Kerr microcomb, in which integrated III-V mode-locked laser outputs short optical pulses to pump the Kerr micro comb. Comparing to existing method, our proposed method could significantly reduce the pumping threshold and improve the conversion efficiency, resulting in integrated, high performance and energy-efficient frequency comb for telecom and RF applications.