Integrated frequency comb generator for clock and carrier dissemination

光学频率梳（OFCs）已经彻底改变了计时、光谱学和计量学领域。十年前发现的OFCs可以在形成明亮耗散克尔孤子的光学微谐振器中产生。这些类型的ofc被称为“孤子微梳”，已经在系统级应用中使用。同时，用于微梳生成的光子集成平台也取得了实质性进展，其中III-V集成锁模激光器和基于Si3N4的Kerr comb[3]已成为有前景的平台。然而，在连续波抽运的情况下，种子信号到梳状音的转换效率较低。这就造成了低功率、低信噪比的梳频，阻碍了克尔梳在光通信、微波光子学、光电仪器等领域的应用。为了克服这些限制，我们将集成III-V锁模激光器[4]与Kerr微梳相结合，其中集成III-V锁模激光器输出短光脉冲泵浦Kerr微梳。与现有方法相比，该方法可以显著降低抽运阈值，提高转换效率，为电信和射频应用提供集成、高性能和节能的频率梳。

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.