Optical power splitters(OPSs)are essential components in the photonic integrated circuits.Considerable power splitting schemes have been reported on the silicon-on-insulator platform.However,the corresponding device lengths are enlarged,and polarization-sensitive operations are usually encountered when the splitting channels are increased from two to five.In this paper,a novel power splitting model is proposed to overcome these limitations.Here,fan-out bending subwavelength grating(FBSWG)metamaterials instead of classical straight SWGs are leveraged to expand the input TE/TM mode in an ultracompact region and further bend its wavefronts.By using N-angled tapers to match bending wavefronts,the light expanded by FBSWGs can be collected and evenly dis-tributed into N output channels.Based on such a model,three OPSs are designed and experimentally demon-strated,which are the shortest polarization-independent 1 x 3,1×4,and 1x5 OPSs reported until now to our knowledge.The characterizations show low insertion losses(＜1.2 dB,＜1.35 dB,and＜1.65 dB)and uniform-ities(＜0.9 dB,＜1 dB,and＜1 dB)over bandwidths of 54 nm,49 nm,and 38 nm for the 1 x 3,1×4,and 1x5 OPSs,respectively.For the first time,an ultracompact device length of＜4.3 μm and a polarization-independent operation can be maintained simultaneously as the output splitting channels are increased.

ZHENZHAO GUO;JINBIAO XIAO;SHENGBAO WU

Photonics Information Innovation Center,Hebei Provincial Center for Optical Sensing Innovations,College of Physics Science and Technology,Hebei University,Baoding 071002,China;National Research Center for Optical Sensing/Communications Integrated Networking,School of Electronic Science and Engineering,Southeast University,Nanjing 210096,China

光子学研究（英文）

[1]ZHENZHAO GUO;JINBIAO XIAO;SHENGBAO WU-.Ultracompact,polarization-independent,and highly scalable optical power splitting model employing fan-out bending metamaterials)[J].光子学研究（英文）,2022(11):2448-2459

Ultracompact,splitters,OPSs,FBSWG,SWGs,ultracompact,FBSWGs,1x5

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