Hybrid heterostructure with a nanolayer of diluted GaIn(Mn)AsSb compound in a type II broken-gap heterojunction

Nanotechnology of obtainment of diluted magnetic semiconductors based on the GaInAsSb compounds is developed using the pulsed laser ablation deposition of Mn atoms on the surface of the epitaxial layer of a quaternary alloy obtained by liquid phase epitaxy. Fabricated heterostructures were studied using high-resolution X-ray diffraction for the Bragg and grazing diffraction geometries, and the depth profiling analysis was performed by secondary ion mass spectrometry. It was established that the nanoscale region of the Ga_0.96In_0.04As_0.11Sb_0.89 epilayer near the deposition surface of atomic Mn exhibits the presence of a quinary compound with Mn atoms in the lattice of the solid solution layer.     

Analysis on thermal characteristics of annular beam pumped vertical-external-cavity surface-emitting lasers by finite element method

The annular beam as a pump light of VECSELs is presented for the first time in this study. The thermal characteristics of VECSELs were calculated and simulated by finite element method, and the influence of the annular beam's annulus radius, the annulus width, and the pumping power to the VECSELs’ thermal characteristics was analyzed in detail. The results indicated that the annular beam can improve the VECSELs’ thermal characteristics efficiently, and provide a favorable term to generate laser in the central part of the annular. The theoretical results provided theoretical reference and experimental study for the design of high-power optically pumped VECSELs.     

Applicability of Time Integrated Spectroscopy Based on the Microscopic Beer-Lambert Law to Finite Turbid Media with Curved Boundaries

Finite curved boundaries are unavoidable in the practical field of non-invasive tissue spectroscopy. This being the case, a technique derived from the microscopic Beer-Lambert law (MBL) can be applied regardless of what geometry is assumed. Here, experimental tests on a type of time integrated spectroscopy based on the MBL for a tissue-like phantom with curved boundaries are presented. The experiments employed a cylindrical liquid phantom 56 mm in diameter, which resembles a human forearm. Two independent measurements were made on the surface of the phantom at various absorption levels (the absorption coefficients of the phantom were from 2.45 × 10⁻³ to 4.12 × 10⁻² mm⁻¹ at 782 nm), one in the direction along the circumference and the other along the long axis of symmetry. In both cases, the absorber concentrations were successfully recovered within error values of a few percent using a single equation.     

Stability conditions of a laser cavity with gaussian diaphragms

Laser cavities with spherical mirrors and Gaussian diaphragms have been investigated. The influence of the parameters of mirrors and Gaussian diaphragms on the stability conditions of such cavities is shown. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 4, pp. 465–468, July–August, 2000.     

角锥棱镜和柱面镜的技术表述与检测

针对近年来应用颇多的两种较特殊的光学元件——角锥棱镜和柱面（透）镜技术表述的不同形式，为使之逐渐趋于规范和统一，参照国外现行的一些技术要求以及国内公司几年来实施的具体事例，给出若干说明、建议、指标和数据处理方法，尤其推荐用光束平行差的均方差来替代最大光束平行差的指标，是评定角锥棱镜技术特性中一项关键的新指标。     

Synthesis of Copper Oxide Hierarchical Nanostructures

The copper oxide (CuO) hierarchical nanostructures were synthesized by a simple hydrothermal reaction, using copper(II) acetylacetonate and NaOH as the reactants. The morphologies of CuO nanostructures are strongly influenced by the dosage of copper(II) acetylacetonate, alkali concentration and reaction temperature. The possible formation process was also discussed on the basis of time‐dependent experiments. This simple solution‐phase method may be useful for morphological synthesis of other oxides nanocrystals.     

诱导式受激布里渊散射相位共轭腔

The theory of ultrafast nonlinear interferometer which is a single-arm interferometer based on a semiconductor laser amplifier is described in Jones matrix. The device is suitable to be a demultiplexer in future optical time-division-multiplexing systems, which utilizes the phase shift induced by the refractive index nonlinearities of SLA.     

激光诱导扩散区的温度监控

激光诱导扩散中的曝光区大小为１０μｍ量级，其温度分布的测量是较困难的。本文报道一我中极微小面积的不接触及控制。文中介绍测控原理、实验装置，给出测量结果。     

碳点的高性能化和功能化改性:方法、特性与展望

碳点作为一种新型碳纳米材料,由于其出色的光学性能、低毒性、良好的生物相容性和易修饰性而被广泛应用于各个领域。为了满足不同领域的需求,几种用以调控碳点光学性能的方法已被提出,例如杂原子掺杂、半导体量子点掺杂、聚合物钝化和改性以及主-客体构建。其中,杂原子掺杂是通过单原子或多原子引入电子给体或受体改变其相邻碳原子的电子密度来增加荧光强度;半导体量子点也可与碳点进行复合提升电子分离效率而起到荧光增强的效果;就聚合物改性而言,聚合物不仅可以对碳点表面实施钝化和功能化,而且其固态(或固化)薄膜可以提供紧密的空间促进碳点表面的辐射跃迁起到荧光增强的效果。此外,由碳点-染料和多孔材料-碳点构成的两种主要的主-客体结构中,前者不仅对碳点的荧光发射强度有着促进的作用,更使得碳点具备了显著的红/近红外荧光发射性能,后者对固态发光碳点不仅提供了可能性和设计的灵活性,且为打开碳点新的应用领域提供了机会。本文将围绕四种碳点功能化的方法逐步展开讨论,并介绍相应碳点的光学性能、发光机理和潜在应用;论述功能化碳点的研究现状,并展望功能化碳点的研究方向。     

Molecular Modification of Benzophenone Derivatives for Lower Bioenrichment and Toxicity Through the Pharmacophore Model

In this study, we used the improved extreme-difference normalization method to calculate the comprehensive evaluation values of bioenrichment and toxicity of benzophenone UV light absor-bers(BPs). Based on this parameter, a 3D-QSAR(QSAR=quantitative structure activity relationship) pharmacophore model was constructed using Discovery Studio software and applied to the mole-cular modification of BPs. With three commonly used ingredients in sunscreen 2-hydroxy-4-methoxybenzophenone(BP-3), 2,2'-dihydroxy-4,4'-dimethoxybenzophenone(BP-6) and 2,2'-dihydroxy-4-methoxybenzophenone(BP-8) as target molecules, we performed BPs substitution reaction based on the binding positions of characteristic elements of the pharmacophore model and designed BP derivatives with reduced bioenrichment and toxicity. Stability and function evaluation showed that while the stability of 6 BP derivatives was enhanced, the light absorption capacity was also significantly enhanced(from 9.16% to 43.16%). Molecular dynamics simulation results showed that the binding ability of BP-609 molecule with serum albumin was reduced by 16.37% compared with BP-6, and the binding with collagen could not occur spontaneously, which could be used as an explanation for the simultaneous reduction of its bioenrichment and toxicity. Besides, through the simulation of human metabolism, it was found that the liver metabolites of BP-609 were less toxic, which reduced the potential risk of human metabolism. It proved that the molecular modification scheme of BPs was environment-friendly.