CMOS-compatible high-index doped silica waveguide with an embedded silicon-nanocrystal strip for all-optical analog-to-digital conversion

作     者：YUHUA LI KUN ZHU ZHE KANG WAI LOK HO ROY DAVIDSON CHAO LU BRENT ELITTLE SAI TAK CHU 

作者机构：Department of PhysicsCity University of Hong KongHong KongChina Photonics Research CentreDepartment of Electronic and Information EngineeringThe Hong Kong Polytechnic UniversityHong KongChina QXP Technology Inc.Xi’an 710119China State Key Laboratory of Transient Optics and PhotonicsXIOPMCASXi’an 710119China 

出 版 物：《Photonics Research》 (光子学研究（英文版）)

年 卷 期：2019年第7卷第10期

页      面：1200-1208页

核心收录：

学科分类：080902[工学-电路与系统] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

基　　金：Research Grants Council,University Grants Committee(GRF 11213618) Strategic Priority Research Program of the Chinese Academy of Sciences(XDB24030300) 

主　　题：waveguide optical pumped 

摘      要：Passive all-optical signal processors that overcome the electronic bottleneck can potentially be the enabling components for the next-generation high-speed and lower power consumption systems. Here, we propose and experimentally demonstrate a CMOS-compatible waveguide and its application to the all-optical analog-to-digital converter(ADC) under the nonlinear spectral splitting and filtering scheme. As the key component of the proposed ADC, a 50 cm long high-index doped silica glass spiral waveguide is composed of a thin silicon-nanocrystal(Si-nc) layer embedded in the core center for enhanced nonlinearity. The device simultaneously possesses low loss(0.16 dB/cm at 1550 nm), large nonlinearity(305 W^-1∕km at 1550 nm), and negligible nonlinear absorption.A 2-bit ADC basic unit is achieved when pumped by the proposed waveguide structure at the telecom band and without any additional amplification. Simulation results that are consistent with the experimental ones are also demonstrated, which further confirm the feasibility of the proposed scheme for larger quantization *** demonstrated approach enables a fully monolithic solution for all-optical ADC in the future, which can digitize broadband optical signals directly at low power consumption. This has great potential on the applications of high-speed optical communications, networks, and signal processing systems.