Lund模型和极端相对论系统的量子能谱

讨论极端相对论量子系统的能谱问题.从给出一个典型的极端相对论系统(Lund模型)的精确解及证明一个新的维里定理这两方面来演示了动能形式对能谱的影响. 关键词：     

多层金属纳米点阵的制备及其光学性质的研究

采用纳米球刻蚀法结合热蒸发技术制备了银和氧化硅交替层叠的纳米颗粒阵列. 扫描隧道显微镜测量结果表明, 该纳米阵列呈锥形多层结构. 分光光度计测量样品表明, 该纳米阵列在近红外波段存在明显的透射谷, 该透射谷来源于金属纳米颗粒局域等离激元的激发, 随着金属/介质层数的增多, 透射谷的位置向短波方向移动. 利用HFSS软件对该纳米阵列进行了仿真, 并分析了透射谷蓝移的原因. 关键词： 纳米球刻蚀技术 金属/介质纳米颗粒 表面等离子激元     

Multi-Band Absorption Properties and Near-Field Enhancement in Mid-Infrared Based on the Interference Theory

We numerically study the multi-band absorption properties and near-field enhancement inside the microcavity based on the interference theory. The compact single unit cell consists of a gold square patch placed on the top of a metallic ground plane, separated by a dielectric layer. At the normal incidence of electromagnetic radiation, four bands of a maximum absorption of 98% are accomplished by appropriate sizes of the square patch. Furthermore, we demonstrate that the four bands, which are corresponding to the fundamental mode and higher modes of the standing wave, can be readily tuned in the mid-infrared region and associated with the near-field enhancement in the cuboid mierocavity. Since chemical and biological fingerprints of the common functional groups can be found in the mid-infrared region, we may readily tune the multi-bands of interest in the mid-infrared range and identify the molecular stretches of groups. Moreover, the proposed structure is insensitive to the polarization of the incident wave due to the complete rotational symmetry （C4 symmetry）. The unique properties of the optical metamaterial indicate that this approach is a promising strategy for surface-enhanced infrared absorption spectroscopy and for the tracking of characteristic molecular vibrational modes