2014年4月14日发表在重要期刊Advanced Optical Materials上（Zhen Chai, Xiaoyong Hu, Yu Zhu, Sibai Sun, Hong Yang and Qihuang Gong, “Ultracompact Chip-Integrated Electromagnetically Induced Transparency in a Single Plasmonic Composite Nanocavity”, Advanced Optical Materials 2, 320 (2014)），并被选为同期的封面文章。博士生柴真是论文第一作者。
表面等离激元感应透明类似于经典的电磁感应透明，在非线性光学和集成光子器件领域具有重要应用。目前国际上在该领域的实验研究中存在的难题是，难以在平行于金属微纳结构表面的平面内实现芯片上可集成的表面等离激元感应透明。这就严重限制了表面等离激元感应透明在集成光子回路和集成光子器件中的应用。
研究论文设计出一种支持多种表面等离激元共振的新型复合微腔，将微腔特征尺寸减小了一个数量级，仅为600nm。通过将复合微腔刻蚀在集成光子回路中，利用单个复合微腔所支持的辐射模式与非辐射模式的相干耦合，直接在集成光子回路中实现了平面内片上集成的表面等离激元感应透明。还通过在复合微腔表面覆盖一层80 nm厚的PMMA薄膜，得到了两个表面等离激元感应透明窗口。研究工作不但有助于推动基于表面等离激元感应透明的微纳集成光子器件的研究，而且为非线性光学效应和现象的研究提供了一个平台。
上述工作得到国家973项目、国家自然科学基金委“创新研究群体”和“杰出青年基金”项目以及介观物理国家重点实验室的资助。
Chip-integrated Plasmon-Induced Transparency in a Single Plasmonic Composite Nanocavity
Plasmon-induced transparency, analogue of classical electromagnetically induced transparency, has attracted enormous attention because of its potentially important applications in the fields of integrated photonic devices and ultrahigh-speed information processing chips. Nowadays, the international problem in the field of PIT and applications lie in that it is difficult to realize chip-integrated PIT in the plane parallel the surface of metallic microstructures. This has seriously restricted the study of ultrahigh speed and chip-integrated information processing based on PIT.
Gong’s group proposes an ultracompact on-chip PIT by using single surface plasmon composite microcavity. Small lateral dimension of 600 nm is obtained for the composite nanocavity, which is reduced by one-order of magnitude compared with previous reports. A large shift of 490 nm in the central wavelength of the transparency window is obtained through coating an organic poly(methyl methacrylate) layer. An additional plasmon-induced transparency like effect is achieved in the near-infrared range through coating the poly(methyl methacrylate) cover layer. The research is reported as a cover article in the journal of Advanced Optical Materials (Zhen Chai, Xiaoyong Hu*, Yu Zhu, Sibai Sun, Hong Yang and Qihuang Gong,* “Ultracompact Chip-Integrated Electromagnetically Induced Transparency in a Single Plasmonic Composite Nanocavity”, Adv. Optical Mater. 2, 320 (2014)). This work not only paves a way for the realization of integrated photonic devices, but also opens up the possibility for constructing ultrahigh-speed information processing chips based on plasmonic circuits.
The above works are supported by the Creative Research Group Project of the National Natural Science Foundation of China, the National Basic Research Program of China and the State Key Laboratory of Mesoscopic Physics.
