Octave-spanning microcomb generation in 4H-silicon-carbide-on-insulator photonics platform  

作　　者：Lutong Cai Jingwei Li Ruixuan Wang Qing Li 

机构地区：[1]Department of Electrical and Computer Engineering,Carnegie Mellon University,Pittsburgh,Pennsylvania 15213,USA

出　　处：《Photonics Research》2022年第4期870-876,共7页光子学研究（英文版）

基　　金：Division of Electrical,Communications and Cyber Systems(2127499);Defense Advanced Research Projects Agency(D19AP00033).

摘　　要：Silicon carbide has recently emerged as a promising photonics material due to its unique properties, including possessing strong second-and third-order nonlinear coefficients and hosting various color centers that can be utilized for a wealth of quantum applications. Here, we report the design and demonstration of octave-spanning microcombs in a 4H-silicon-carbide-on-insulator platform for the first time, to our knowledge. Such broadband operation is enabled by optimized nanofabrication achieving >1 million intrinsic quality factors in a 36-μm-radius microring resonator, and careful dispersion engineering by investigating the dispersion properties of different mode families. For example, for the fundamental transverse-electric mode whose dispersion can be tailored by simply varying the microring waveguide width, we realized a microcomb spectrum covering the wavelength range from 1100 nm to 2400 nm with an on-chip power near 120 mW. While the observed comb state is verified to be chaotic and not soliton, attaining such a large bandwidth is a crucial step towards realizing f-2f self-referencing.In addition, we also observed a coherent soliton-crystal state for the fundamental transverse-magnetic mode,which exhibits stronger dispersion than the fundamental transverse-electric mode and hence a narrower bandwidth.

关 键 词：SPANNING INSULATOR utilized 

分 类 号：TQ163.4[化学工程—高温制品工业] O43[机械工程—光学工程]