"Studies on Tuning of Photonic Crystal Characteristics after Fabrication"

（1）电子束辐照二维柱状结构的位置控制及其激光作用利用GaAs/Al_1GaAs多层结构的干法刻蚀制备了二维柱状结构光子晶体。在扫描电镜装置中用电子束辐照，观察到规则排列的晶格发生局部变形和聚束。这种现象进行了分析库仑吸引力和排斥力的平衡。结果表明，库仑力足以使直径为0.3 μm、长度为1μm的柱状体产生永久变形。根据输出光功率与激发功率的关系，确认该晶体的激发阈值为100 mW。激光波长在计算的光子带隙的较高能量边缘，其中GaAs的光学增益带和光子晶体的光学增益带在较高能量边缘处。 ...更多信息 nic带隙交叉。（2）组合结构光子晶体的制备与评价上述具有调谐机制的光子晶体结构的一个缺点是，虽然基本材料是半导体，但干法刻蚀损伤导致光学增益差。为了克服这一问题，将介质光子晶体与半导体多层结构相结合。即在表面具有二维缺陷的半导体MOW结构上生长SiO_2/Si三维光子晶体。通过多量子阱波导传输的光致发光受到过生长光子晶体的影响，并出现新的发光峰，这是由于多量子阱光增益和光子晶体周期性的相互作用。除了半导体衬底外，还成功地使用了通过铝金属阳极氧化制备的氧化铝霍尔阵列。（3）利用光子晶体光纤产生超连续光我们已经注意到光子晶体光纤包层中的非常小的纤芯，它们是无意产生的，即所谓的伪纤芯。采用特殊设计的耦合光学系统，使脉冲宽度小于1 ps的钛宝石脉冲激光击中特定的赝核成为可能。获得了450 ~ 1400 nm范围内的超连续谱光。由于赝纤芯的尺寸非常小，即使是亚毫米长的光纤也能够产生超连续谱光，这是据我们所知的最短长度的超连续谱光产生。用硅光刻法制作了35μ m长的SiO2空气悬丝，初步观察到了超连续谱光。少

(1)Position control of 2D pillar structure by electron beam irradiation and their lasing actionPhotonic crystal with 2D pillar structure is fabricated by dry etching of GaAs/A1GaAs multi-layered structure. By irradiation of electron beam in the SEM apparatus, it observed that regularly arranged lattice was deformed and bunched locally. This phenomenon is analyzed in terms of the balance of Coulomb attractive and repulsive forces. It was found that the Coulomb force is enough strong to give permanent deformation to the pillar with the dimensions of 0.3 μm diameter and 1μm long.Lasing characteristics were investigated on the 2D photonic crystal mentioned above using Ti-Sapphire laser as an excitation source. It was confirmed that the crystal lased with the excitation threshold of 100mW based on the dependence of output light power on excitation power. The lasing wavelength was at the higher energy edge of the calculated photonic band gap, where the optical gain band of GaAs and the photo … More nic band gap cross over.(2)Fabrication and evaluation of the combined structure photonic crystal and semiconductorAbove-mentioned photonic crystal structure with tuning mechanism has a weak point that dry etched damage results in poor optical gain although basic material is semiconductor. To overcome this problem, dielectric photonic crystal was combined with semiconductor multiplayer structure. That is, SiO_2/Si 3D photonic crystal was grown on semiconductor MOW structure with 2D corrugation on their surface. Photoluminescence propagating through MQW waveguide was affected by the presence of overgrown photonic crystal and showed new luminescence peak resulted from interaction of MOW optical gain and periodical feature of the photonic crystal. In addition to the semiconductor substrate, aluminum oxide hall array fabricated by anodic oxidization of aluminum metal was successfully used.(3)Supercontinuum light generation through photonic crystal fiberWe have paid attention to the very small cores in the cladding of photonic crystal fiber, which are unintentionally generated and so-called pseudo core. Using specially designed coupling optics it became possible to hit the specific pseudo core by Ti-Sapphire pulse laser with pulse width less than 1ps. The supercontinuum light raged from 450nm to 1400nm was obtained. Since the size of the pseudo core is so small even sub-mm-long-fiber is able to produce the supercontinuum light, which is, to our knowledge, the shortest length of supercontinuum light generation. It was preliminarily observed the supercontinuum light with 35μm-long-SiO2 air suspended wire fabricated by Si photolithography. Less