An angle-resolved laser incident beam detector based on a pair ofFabry-Perot etalons

An angle-resolved laser detector based on a pair of a non-mechanical scanning Fabry-Perot cavities is described. The differential signal from the two cavities is approximately independent from the polarization of the incident laser beam and it is used to determine the angle of incidence of the beam on the Fabry-Perot cavities. The F-P etalon is made of interferometric filter combination. A laser incident angle sensor experimental platform is built up, and the experiment is carried out with a given laser range finder. When the incident angle is less than 5°, the transmission difference measured by the laser angle sensor is significantly lower than theoretical value, and deviation is more than 10%. When the incident angle is greater than 10°, the deviation is much lower than that of the situation of the incident angle is lower than 10°.     

Experimental determination of two-point Stokes parameters for a partially coherent broadband light beam

The generalized Stokes parameters, which are two-point extensions of conventional Stokes parameters, are determined for a pair of points in the cross-section of a partially coherent broadband light beam. For this purpose, using a two-mirror and two-beam-splitter assembly, unpolarized, linearly polarized and partially polarized electromagnetic beams are generated. This simple experimental method for determining generalized Stokes parameters establishes an analogy with the experimental scheme of determining conventional Stokes parameters, which in succession contributes to appreciable reduction in uncertainty in the measurements.     

Effect of spontaneously generated coherence on probe response in an open system

The effect of spontaneously generated coherence on the probe response in an open ladder atomic system with equispaced levels is studied. The result shows that by adjusting the strength of spontaneously generated coherence (SGC), electromagnetically induced transparency (EIT) and high dispersion (index of refraction) with zero absorption can be realized, a much larger gain without inversion (GWI) than that without SGC can be obtained. Moreover, in the open system and for some strength of SGC, GWI without the incoherent pumping is much larger than that with the incoherent pumping; however, in the corresponding closed system, when the incoherent pumping is absent, we cannot obtain any gain (with or without inversion) for any strength of SGC. In addition, the manipulation role of the atomic exit and injection rates on SGC-dependent absorption property is analyzed for the case when the incoherence pumping does not exist.     

Minimization of Interferences in Flow Injection Amperometric Glucose Biosensor Based on Oxidation of Enzymatically‐produced H2O2

One of the major problems in amperometric biosensors based on detection of H₂O₂ produced by enzymatic reaction between oxidase enzymes and substrate is the interference of redox active compounds such as ascorbic acid (AA), dopamine (DA) and uric acid (UA). To minimize these interferences, sodium bismuthate was used for the first time as an insoluble pre‐oxidant in the flow injection (FI) amperometric glucose biosensor at a Glucose oxidase (GOx) immobilized Pt/Pd bimetallic modified pre‐anodized pencil graphite electrode (p.PGE). In this context, these interfering compounds were injected into a flow injection analysis (FIA) system using an injector which was filled with NaBiO₃. Thus, these interferents were converted into their redox inactive oxidized forms before reaching the electrode in the flow cell. While glucose was not influenced by the pre‐oxidant in the injector, the huge oxidation peak currents of the interferents decreased significantly in the biosensor. FI amperometric current time curves showed that the AA, DA and UA were minimized by 96 %, 86 %, and 98 % respectively, in the presence of an equivalent concentration of interferences in a 1.0 mM glucose solution. The proposed FI amperometric glucose biosensor exhibits a wide linear range (0.01–10 mM, R²=0.9994) with a detection limit of 2.4×10^?3 mM. Glucose levels in the artificial serum and two real samples were successfully determined using the fabricated FI amperometric biosensor.     

Coherent hole-burnings induced by a bichromatic laser field

In a Doppler-broadened three-level Λ-type system driven simultaneously by a coupling laser and two equal-amplitude saturating laser fields with a frequency difference 2δ, the absorption spectrum of a weak probe laser exhibits multiple deep spectral holes through coherent hole-burning CHB with controllable numbers, widths, depths, and positions. More significant, changing δ or lasers directions, CHBs can degenerate into narrower and deeper spectral holes where the slope of the refractive index is very steep. The multiple narrow spectral holes in a single absorption profile are expected to have potential applications in high density storage, optical information processes, and slow-light.     

Property of Image-Object Using TE/TM-polarized Wave in the Near-Field Optics with CCGM-FFT

Discretization of the Lippmann-Schwinger integral equation with complex conjugate gradient method and fast Fourier transform （CCGM-FFT） is solved, which can reduce the memory storage and the CPU time compared with the traditional method, MOM. Thus objects with large size and multiple scattering objects could be simulated with CCGM-FFT. The total intensity and the distribution of each field component of the dielectric and metallic objects under the excitation of the TE//TM-polarized wave are calculated with photon scanning tunnelling microscopy （PSTM） at the constant height. The simulating results are analysed and explained reasonably. The results show that the polarization plays an important role for imaging of PSTM.     

应力长周期光纤光栅透射谱中旁瓣的抑制

提出一种优化应力长周期光纤光栅的实验方法.利用自行研制的机械结构,通过点接触施力写制应力长周期光纤光栅,并通过压力板V-M型形变实现优化MLPFG传输谱的n维调节,有效抑制了应力长周期光纤光栅传输谱中的旁瓣.当损耗峰LP05损耗强度为9.0 dB时,边模抑制比大于8.6 dB;同时,提出并实现了一种通过空气薄层形成的等厚干涉条纹来监测光纤上力分布的光学方法,从而为传输谱的优化提供有效参量.     

利用光纤法布里-珀罗谐振器干涉透射波长同时测量混合溶液中多溶质浓度

为了同时探测混合溶液中多种溶质的浓度,提出一种用光纤法布里-珀罗谐振器作为传感器测量混合溶液中多溶质浓度的测量系统.从理论上分析了光纤法布里-珀罗谐振器干涉透射波长与混合溶液浓度之间的关系,采用光纤法布里-珀罗谐振器干涉透射波长实现了高准确度同时测量混合溶液中多溶质浓度的原理和可行性.构建了由InGaAs发光二极管光源、光纤耦合器、FFPR传感器、光电信号转换和放大器、光谱分析仪等组成的测量系统.对乙醇和甘油的9组标准混合溶液进行测量实验,并用测量结果标定了混合溶液中各溶质浓度与光纤法布里-珀罗谐振器传感器干涉透射波长之间的数学解析关系式.根据数学关系式用Action Script 2.0脚本语言编写程序,计算机实时监控了混合溶液中各溶质浓度的变化过程.     

氢化物发生辅助溶液阴极辉光放电光谱技术检测水体中痕量汞和锡

溶液阴极辉光放电技术作为一种新型的光谱检测技术,被广泛应用于环境污染物的分析和检测等方面.虽然该技术具有结构简单以及成本低等优势,但是在重金属检测方面,其灵敏度还有待提高.针对上述问题,搭建了氢化物发生-溶液阴极辉光放电光谱测量系统,实现了对水体中痕量汞(Hg)和锡(Sn)的简单高效检测.为了得到更优的检测效果,实验选...     

干涉博弈的定义及性质

本文从石油输出国家组织 - OPEC提出限制原油产品的背景出发 ,提出干涉博弈的概念 :当给出博弈 v(M)≤ q,q∈ R的约束条件时 ,原博弈 v(S)变成一个新的博弈 -干涉博弈 vq.证明了当 q≥ i∈ Mv({ i} ) ,xi ≥ v(M)q v({ i} )时 ,vq的稳定集非空 ,vq是相对稳定的 ;当 q < i∈ Mv({ i} )时 ,该博弈的分配是不存在的 ,导致其稳定集是空集 ,vq 是不稳定的 .