罗丹明B同步荧光猝灭法测微量磷的条件研究

本文研究了罗庆明Ｂ－磷钼杂多酸离子缔合物体系的荧光特性及测定方法，对实验条件进行了优化选择，并引入非离子表面活性剂ＯＰ对体系增敏，增稳。本法用于黑色食品中磷的测定，结果满意。     

基于环行腔激光器四波混频型可调谐波长转换的理论研究

建立了完整的基于半导体环行腔激光器四波混频型可调谐波长转换器的宽带理论模型.模型中考虑了半导体光放大器的材料增益谱、载流子的空间分布、光场的纵向空间分布和宽带放大自发发射等关键因素，并通过数值模拟，从理论上研究了这种波长转换器的各种性能与输入信号光功率、注入电流、输出耦合器的耦合比和环行腔激光器激射光波长的关系.理论上所得结论与文献中实验结果符合得很好. 关键词： 半导体环行腔激光器 四波混频 波长转换 放大自发发射     

Analytical modelling of carrier transport mechanisms in long wavelength planar n+–p HgCdTe photovoltaic detectors

The dark electrical characteristic of n⁺ on p long wavelength Hg_1−xCd_xTe photovoltaic detectors has been studied as a function of applied bias voltages. The diodes under study were given different surface treatments prior to their passivation. The dark current components have been identified using the already known carrier transport mechanisms across the junction. It is reported that the diodes under investigation have an excess leakage current component that exhibits quadratic dependence on the applied reverse bias voltage across the diode. The origin of this excess current is found to be closely associated with the ohmic currents. The diodes with higher ohmic current exhibit higher excess leakage current.     

台阶高度测量方法研究现状及进展

台阶高度测量是目前新提出的国际计量比对项目之一,当前的趋势是向纳米量级精度发展并尽量扩大测量范围。在分析现状和背景的基础上,大致归类了测量台阶高度的几种光学方法,着重介绍了其中绝对干涉方案的最新进展,从测量原理、测量精度以及量程等几方面比较了它们的优缺点。在此基础上提出以可调谐半导体激光器作为光源,采用可调合成波长链法实现纳米级精度毫米级量程的台阶高度测量,详细分析了方案的原理误差,得到最后的结论。     

Intersubband energies in Al1−yInyN/Ga1−xInxN heterostructures with lattice constant close to aGaN

We have studied the conduction band profile and the intersubband transition energy, E₁₂, of Al_1−yIn_yN/Ga_1−xIn_xN quantum well structures. We have considered how material parameters such as non-parabolicity and the uncertainty in the bowing parameter affect E₁₂ and the corresponding wavelength, λ₁₂. The calculations include strain and cover the transition range from telecommunication wavelengths (1.55 μm) to the mid-infrared (∼ 10 μm).     

基于光谱探测的战场目标快速识别

基于光谱探测的目标识别技术，因其能够对抗伪装目标、抗干扰性强等优势，已经逐步应用于军事领域，为战场目标识别提供了一个新思路。该方法的重点在于光谱识别的准确性、数据处理技术等等，目前对于该方法的研究、改进以及创新多基于上述重点进行的。现代战争的复杂程度越来越高、可预见性越来越低，所以对于战场机会的把握成为了能否打赢现代战争的关键，因此对于应用于战场的目标识别方法的实时性要求将越来越苛刻。故重点集中在基于光谱识别的目标识别方法的实时性，目的是为了实现快速的目标识别，使得该方法能够适应现代战争的作战特点，增强其实用性。首先对该研究的必要性进行分析；然后以偏振干涉成像光谱仪为例，说明该工作的改进之处并对提高目标的实时性进行原理分析；最后对下一步的工作重点以及应用领域进行分析，简述发展前景。     

In-Phase Wavelength Conversion Based On Cross-Gain Modulation in Semiconductor Optical Amplifier

In-phase wavelength conversion based on cross-gain modulation in a semiconductor optical amplifier biased around critical threshold current has been demonstrated. The converted signal and the pump signal have the same bit sequence 1101011000. The stimulated emission competition between the amplification of input signals and the amplified spontaneous emission was used to illustrate the conversion mechanism. Experiment results showed that in-phase wavelength conversion can be achieved with simple structure and high output extinction ratio.     

Wavelength Switching of a Fabry-Perot Semiconductor Laser by Optical Input Pulses

Wavelength switchings of a Fabry-Perot semiconductor laser are experimentally demonstrated by applying externally optical input pulses detuned from a cavity-resonant wavelength of the semiconductor laser with a constant injection current. The wavelength region of optical switching ranges from less than 0.1 nm to several nm over gain spectrum, being locked to the wavelength of optical inputs. These behaviors are based on multistability and multi-split branches in the optical output versus detuned optical input characteristics, caused by the carrier-induced refractive index change accompanied by optical injections. The experimental results are believed to be useful for wavelength division multiplexing and exchange in optical communication.     

Design of Simple Wavelength or Polarization Filter/Combiner

We present an analytical and numerical analysis of a simple wavelength or polarization filter/combiner constructed from three single-mode rectangular waveguides. The device has the advantage of easy fabrication using existing planar light guide techniques and can be designed to discriminate between optical signals with distinct polarizations at a given wavelength or between signals at a fixed polarization with a wavelength separation of 9~nm or more. It is therefore well suited for CWDM metro-communication, local area network, sensor, or control applications.     

不同Tm3＋浓度掺杂碲酸盐玻璃光谱性质研究

制备了70TeO₂-20WO₂-10ZnO-xTm₂O₃系统玻璃，根据所测玻璃的吸收光谱，应用Judd-Ofelt(J-O)理论计算出Tm^3＋离子在碲酸盐玻璃的J-O强度参数、Tm^3＋在玻璃中的自发辐射概率A、荧光分支比β及荧光辐射寿命 τ_R 等各项光谱参数.测定了玻璃的荧光光谱，并计算了Tm^3＋在碲酸盐玻璃中的荧光有效线宽、峰值受激发射截 面.比较了Tm^3＋在不同掺杂浓度下的光谱特性，认为当Tm₂O₃掺杂浓度达到 0.8wt％—1wt%时，所获得的荧光强度与荧光线宽达到最佳值，掺Tm^3＋ 碲酸盐玻璃是一种理想的S波段宽带光纤放大器用基质材料. 关键词： 碲酸盐玻璃 宽带光纤放大器 荧光线宽 荧光峰值发射截面