Wavelength Conversion Efficiency Enhancement in Modal Phase Matched $\chi^{\hbox{{(2)}}}$ Nonlinear Waveguides

IEEE Photonics Journal

Siyuan Yu¹  Dongpeng Kang¹  Weiqi Zhang¹  Jing Ma¹  Liying Tan¹  Amr S. Helmy² 

[1] School of Astronautics and National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin, China;The Edward S. Rogers Department of Electrical and Computer Engineering, Centre for Quantum Information and Quantum Control, University of Toronto, Toronto, ON, Canada;

关键词: Wavelength conversion;    second harmonic generation;    difference frequency generation;    modal phase matching;    compound semiconductor;    Aluminum Gallium Arsenide;   

DOI  :  10.1109/JPHOT.2021.3087606

来源: DOAJ

【 摘 要 】

Modal phase matching (MPM) is a widely used phase matching technique in Al$_x$Ga$_{1-x}$As and other $\chi ^{(2)}$ nonlinear waveguides for efficient wavelength conversions. The use of a non-fundamental spatial mode compensates the material dispersion but also reduces the spatial overlap of the three interacting waves and therefore limits the conversion efficiency. In this work, we develop a technique to increase the nonlinear overlap by modifying the material nonlinearity, instead of the traditional method of optimizing the modal field profiles. This could eliminate the limiting factor of low spatial overlap inherent to MPM and significantly enhance the conversion efficiency. Among the design examples provided, this technique could increase the conversion efficiency by a factor of up to $\sim$290 in an Al$_x$Ga$_{1-x}$As waveguide. We further show that this technique is applicable to all $\chi^{(2)}$ material systems that utilize MPM for wavelength conversion.

【 授权许可】

Unknown