掺杂纳米半导体超微粒ZnS:Mn2+光学特性研究

九十年代对纳米尺寸(nanoscale)材料的光物理性质的深入研究,导致了介于微观与宏观物理间的新的学科一介观物理(mesoscopic physics)的产生.其科学义在于建立和发展介于原子分子和固体之间所谓介观系统(mesoscopic system)的量子理论,揭示介观物质特性及其相互作用本质,并利用介观特性探索新型结构和功能材料.以往对纳米半导体超微粒材料的研究主要集中于与本征特性相关的量子尺寸效应,或缺陷对超微粒本征特性的影响[1,2].超微粒中过渡金属离子中心发光性质研究首次报道于1993年[3,4]并指出这可能成为崭新的一类发光材料.     

Effect of an impurity on 3-electron quantum dots in magnetic fields

1 Introduction Quantum dots (QDs), often referred to as artificial atoms, are currently under in-tense study because they provide ideal structures used in optical-electronic microdevices, so they are essential in developing microtechniques. They are also essential in the aca-demic aspect, because rich information on microstructures can be extracted both theo-retically and experimentally. Since the early fabrication of the QDs, external magnetic field has been used to control their propertie…     

Energetic instability unjams sand and suspension

Jamming is a phenomenon occurring in systems as diverse as traffic, colloidal suspensions, and granular materials. A theory on the reversible elastic deformation of jammed states is presented. First, an explicit granular stress-strain relation is derived that captures many relevant features of sand, including especially the Coulomb yield surface and a third-order jamming transition. Then this approach is generalized, and employed to consider jammed magnetorheological and electrorheological fluids, again producing results that compare well to experiments and simulations.     

Fourier algorithm method for reconstruction of large-aperture digital holograms based on phase compensation

To simplify the reconstruction calculation of a large-aperture digital hologram we propose a novel Fourier-transformation reconstruction algorithm. When the reconstructed wave is the same as or similar to the reference wave, the higher-order phase term of reconstruction can be compensated for. For example, the variation between the higher-order phase term and the aperture angle with a different field of view in in-line phase-shifting digital holography is analyzed.     

Ultrahigh-resolution optical coherence tomography by broadband continuum generation from a photonic crystal fiber

We have developed an ultrahigh-resolution optical coherence tomographic system in which broadband continuum generation from a photonic crystal fiber is used to produce high longitudinal resolution. Longitudinal resolution of 1.3-microm has been achieved in a biological tissue by use of continuum light from 800 to 1400 nm. The system employed a dynamic-focusing tracking method to maintain high lateral resolution over a large imaging depth. Subcellular imaging is demonstrated.     

On Euler products associated with noncuspidal metaplectic forms

In this paper, we obtain an Euler product with functional equation associated to a noncuspidal metaplectic form on the double cover of . Zagier's idea of Rankin-Selberg method is used to define the convolution of and the -function.

     

All optical quasi-steady-state photorefractive spatial solitons

We have created a one- (rather than two-) dimensional quasi-steady-state photorefractive spatial soliton induced by a laser beam instead of an applied electric field. The formation of this type of spatial soliton depends on the intensity of the self-trapped beam, which is different from quasi-steady-state spatial solitons reported in the literature. The optically induced spatial soliton can be exploited in all optical switching applications.     

利用弹簧振子演示李萨如图形

介绍了利用光滑导轨、弹簧振子、高亮发光二极管演示李萨如图形的方法.