Interaction between radiation field and matter in a photonic crystal

1.光子晶体（PC）的发展：我们成功地开发了1）二维（2D）空气棒型PC，2）二维平板（准3D）型PC，和3）有序球体的三维（2D）PC，并揭示了它们的光学性质。分别采用阵列光纤的毛细管法、AlGaAs芯层介质波导的微加工技术、辐射压力和聚苯乙烯颗粒的自组织作用制备了这三种结构。结果发现，1）的光子晶体是第一个在近红外波段具有带隙的光子晶体。与2）相比，我们首次识别了PC平板的导模，并验证了带隙的存在。我们还制作了具有线缺陷的光子晶体，并对缺陷或局域模进行了实验鉴定.光与光子晶体的相互作用：1）利用亚皮秒光脉冲的飞行时间，我们发现光子晶体的群速度vg随着带边的增大而减小 关于我们 接近，并已观察到小至0.05倍c（真空中的光速）的vg值。2)我们首次在二维PC中观察到激光作用。这种现象被解释为产生于一个小的vg，这使得光和物质之间的有效相互作用长度足够长。3)我们的实验表明，所谓的相位匹配是很容易满足在PC中的各种波长，无论是由于其独特的频带色散，或与Umclapp过程的帮助。4)通过研制一台新的高性能光谱仪，我们揭示了一排空气孔缺失的PC平板波导具有优异的光学特性。也就是说，我们明确地确定了缺陷或本地模式的各种组件的设计和制造，如弯曲的，Y-分裂器，定向耦合器，并测量这些传播损耗。为研制未来通信用超高速平面光集成电路奠定了坚实的基础。少

1. Development of photonic crystals (PCs) : We successfully developed 1) two-dimensional (2D) air-rods type PCs, 2) 2D slab (quasi- 3D) type of PCs, and 3) three- dimensional (2D) PC of ordered spheres, and revealed their optical properties. Those were fabricated in this order by using the capillary method for arrayed fibers, the state-of- arts micro-machining technique for the dielectric waveguide with AlGaAs core-layer, and radiation pressure and self-organization of polystyrene particles, respectively. As a result, we find that the PC of 1) is the first one developed with a band gap at near-infrared wavelengths. Ass for 2), we have for the first time identified the guided modes and verified the existence of the band gap for PC slabs. We also fabricated PCs with line defect and identified experimentally the defect or local modes.2. Interaction between light and PC : 1) Using time-of-flight of sub-picosecond light pulse we find that the group-velocity vg is smaller as the band edge is … More approached, and have observed a vg-value as small as 0.05 times c (light velocity in vacuum). 2) We observed for the first time laser action in a 2D PC. This phenomenon is interpreted as arising from a small vg, which makes the effective interaction length between light and matter long enough. 3) We experimentally demonstrated that the so-called phase- matching is easily satisfied at various wavelengths in a PC, either due to its unique band dispersion, or with help of Umclapp process. 4) We have revealed, by developing newly a powerful spectrometer, that PC-slab-based waveguides with a line of air-holes missing show distinguished optical properties. Namely, we identified unambiguously the defect or local modes for a variety of components designed and fabricated, such as abruptly-bent ones, Y-splitter, and directional coupler, and also measured propagation loss of those. As a result, we have provided a firm basis for developing ultra-fast, planar light integrated circuit for future telecommunication use. Less