慢光表面等离子波导吸收损耗问题的研究

Surface plasmonic polariton (SPP)-based slow light is a vital approach to optical buffering and strong optical nolinearity beyond diffraction limit. In this project we will explore the structural design of low-loss slow-light plasmonic waveguides and optimization mechanism to minimize the influence of absorption loss on device performance. Investigation includes, (1) designing the system of metal-dielectric multilayer transmission structure combined with planar patterns; (2) acquiring optimized passive device by trading off the influences of attenuation, group velocity dispersion and attenuation dispersion; (3) elongating propagation length by loss compesation with gain to enhance delay capacity; (4) experimentally investigating SPP transmission characteristics, including attenuation, time delay, group velocity dispersion, transmission bandwidth, etc. The merits of this project lie in (1) adoption of unique waveguide structures to take the loss into account in the design optimization problem, (2) introduction of gain for improving performance of slow-light plasmonic waveguides. As a topic at the forefront, research in SPP-based slow light needs be further developed. Few experimental results have been reported, although there are several reported theoretical studies. The theoretical and expiermental achievements in this project are expected to increase the knowledge on the slow light in plasmonic approach.

表面等离子(SPP)慢光是超衍射极限下的光缓存及强光学非线性的一个重要途径，它的实现有助于光子集成在全光通信中的应用。本项目探索低吸收损耗慢光SPP波导的结构设计及降低吸收损耗对器件特性影响的优化机制，获得优化的宽频带延迟特性。将研究（1）设计金属-介质多层膜传输结构与平面内图形结构结合的体系，有效利用SPP的极化激元特性和波导模式的色散特性带来的设计自由度；（2）对衰减、群速度色散和衰减色散的影响采取折中考虑，获得无源器件的优化结果；（3）通过增益补偿损耗来延长传输长度，提高延迟能力；（4）通过实验研究SPP传输特性，包括衰减、延时、群速度色散及传输带宽等。特色在于（1）采用独特的波导结构在设计优化问题中考虑损耗的影响；（2）引入增益提高SPP慢光波导性能。SPP慢光是有待深入研究的前沿课题，已有一些理论工作报道但实验结果极少，本项目的理论和实验结果将增进人们对SPP慢光途径的认识。

表面等离子(SPP)慢光可用于超衍射极限下的光缓存及强光学非线性，它的实现有助于光子集成在全光通信中的应用。本项目研究了低吸收损耗慢光SPP波导的结构设计及降低吸收损耗对器件特性影响的优化机制，实现了电泵浦辅助SPP传输。重点是探讨了电泵浦量子阱半导体材料对SPP传输损耗的补偿机制，对有源SPP波导结构进行设计优化，实现了对短程SPP模式的传输损耗，之后通过非对称结构对SPP慢光波导色散补偿作用，实现无色散的宽频SPP慢光传输。本项目的研究对延长SPP器件工作距离，增强光学非线性，光通信领域的信号延迟、数据缓存与交换等关键技术有重要意义。