基于氢化非晶硅波导的芯片式简并关联光子对源

项目名称： 基于氢化非晶硅波导的芯片式简并关联光子对源

项目编号： No.11504262

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 杨磊

作者单位： 天津大学

项目金额： 20万元

中文摘要： 简并关联光子对是实现量子计算的重要资源。近年来，量子计算的基本单元C-NOT门也向微型化、大规模集成化发展，因此研制芯片式简并关联光子对源成为当今的研究热点。基于晶体的参量下转换和基于光纤的四波混频是制备简并光子对的有效方法，但这两种光源的兼容性和扩展性较差，不适于在集成光学中的应用。基于硅基光波导的简并光子对源具有芯片化和可大规模集成的应用前景。目前硅基光波导制备简并光子对易受双光子吸收效应的影响，产生效率低；泵浦光源均采用连续光，功率要求高，光子对产生时间不确定，不利于在Hong-Ou-Mandel干涉中的应用。本项目利用氢化非晶硅光波导中的四波混频制备简并光子对，可降低双光子吸收的影响；采用超短脉冲作为泵浦，既提高泵浦的峰值功率又可确定光子对的产生时间；利用Sagnac环实现光子对的空间分离。项目的目标是研制一套基于氢化非晶硅波导产生通讯波段高质量简并光子对的可集成化量子光源。

中文关键词： 简并关联光子对；氢化非晶硅波导；四波混频；Sagnac环；Hong-Ou-Mandel干涉

英文摘要： The degenerate correlated photon pairs is a vital resource in realizing quantum computing. In recent years, the basic component of quantum computing such as C-NOT logic gate which relays on the degenerate photon pairs has developed for miniaturization and large-scale integration. The on-chip source of degenerate correlated photon pairs is therefore become an active research focus. The traditional methods based on the parametric down-conversion (PDC) in nonlinear crystals and four wave mixing (FWM) in optical fibers are effective ways to generate the degenerate photon pairs. However, due to the poor compatibility and scalability, these sources are not suitable for the application in quantum photonic integration. The photon pairs source based on silicon on insulator (SOI) waveguide is considered as a promising candidate for large-scale integration system. In the demonstrated experiments, however, the crystalline silicon was used to generate the correlated photon pairs, which suffers from the two photon absorption and free carries absorption, resulting in low photon pair generation rates. Besides, pumped by the modulated continuous wave also requires high power intensity and affects the creation time of photons that is harmful for Hong-Ou-Mandel interference. In this project, the hydrogenated amorphous-silicon (a-Si:H) waveguide was used for generating the degenerate photon pairs through the process of FWM, which is benificial to eliminate effects of two photon absorption. In addition, the ultrashort femtosecond pulsed laser is also employed as the pump source to improve the peak power as well as determine the creation time of photon pairs. Meanwhile, the Sagnac loop is utilized to splitting the degenerate twin photons into different spatial modes. The aim of this project is developing an on-chip integrated quantum source based on the a-Si:H waveguide, which can produce the degenerate correlated photon pairs on telecommunication band with high brightness and purity.

英文关键词： degenerate correlated photon pairs;hydrogenated amorphous-silicon waveguide;four-wave mixing;Sagnac loop;Hong-Ou-Mandel interference