The application of the Lorentz model and real-cavity model to the dependence of spontaneous radiative lifetime of localized luminescent centers of the surrounding media is analyzed. Various experimental results available in the literature are successfully interpreted with the models applicable to the cases. The criterion as to which model should be applied for a specified case is presented.

Novel Tm3+ and Yb3+ codoped bismuth-germanium-lead glass was fabricated and characterized;the glass sample components are 45Bi2O3-35GeO2-20PbO-0.02Tm2O3-xYb2O3(x= 1.0,1.2,1.4,1.6 and 2.0 mol%). The absorption and upconversion spectra of Tm3+ and Yb3+ codoped in bismuth-germanium-lead glass were investigated,and upconversion mechanisms of Tm3+ in the glass were analyzed. The Judd-Ofelt intensity parameters Ωt(t = 2,4,6),oscillator strengths,spontaneous transition probability and fluorescence branching ratio of each levels for Tm3+ were calculated by Judd-Ofelt theory. Intense blue and weak red emissions centered at 476 and 653 nm,correspongding to the transitions 1G4 →3H6 and 1G4→3F4,respectively,were simultaneously observed at room temperature under 975 nm diode laser excitation. The upconversion emission intensity varies with the power of infrared excitation intensity. A plot of log IUP VS log IIR yields a straight line with slope 2.87 and 2.41,corresponding to the 476 and 653 nm emission bands,respectively,which indicates a three-photon process for the blue and red emissions. The results suggest that Tm3+ and Yb3+ codoped bismuth-germanium-lead glass may be a potential host material for upconversion blue lasers.

The relationship between the optical spectra and the crystal structure parameters is set up,and the local structure parameters of group [Ni(H2O)6]2+ of Ni2CdCl6·12H2O crystal can be determined from the optical spectra at 14 K. The local structure and absorption spectra of Ni2+ ions of Ni2CdCl6·12H2O crystal are interpreted based on superposition model and the complete diagonalization procedure method. According to the calculation,the local structure values of [Ni(H2O)6]2+ are: bond length R ≈ 0.2009 nm and bond angle θ ≈ 55.1°. Theoretical results of optical spectra are in good agreement with experimental findings.

The equilibrium geometries,harmonic vibrational frequencies,natural bond orbital(NBO)charge distributions,and the affinity energies of Li+ attachment to CH3-nFnO2(n = 0～3)have been investigated using ab initio molecular orbital theory and density functional theory(DFT).The structures were determined using unrestricted second order M?ller-Plesset(UMP2)and unrestricted Beck's three-parameter Lee-Yang-Parr(UB3LYP)theories in conjunction with 6-31G(d,p),6-311G(d,p),6-311+G(d,p),6-311G(2d,p)and 6-311+G(2df,2p)basis sets,and the stretching vibrational frequencies were investigated for CH3－nFnO2 and CH3－nFnO2Li+,using optimized geometries at the same levels. The calculated vibrational frequencies of radicals at UB3LYP/6-311G(d,p)levels were consistent well with the experimental data. The affinity energies of Li+attachment to CH3－nFnO2(n = 0～ 3),calculated by DFT and ab intio are all large which suggest that CH3－nFnO2Li+ complexes could be possibly detected as stable species in gas phase by ion attachment mass spectrometry.

Theoretical model of an open four-level atomic system driven by two fields was presented. The density matrix equations of motion were obtained by the electric dipole and the rotating wave approximations. Under resonance of corresponding fields,the physical mechanism of lasing without inversion(LWI)was discussed and its linear analytical solution was obtained. By numerical results,we studied the effects of the spontaneous decay rates between atomic levels,incoherent pump rate,the injection rates,and the exit rate on the gain without inversion and the population difference of the system. The difference between the linear and nonlinear gain and the population difference of the system were discussed. A LWI gain was got during the region of the spontaneous decay rates between atomic levels. The LWI gain can obtain by adjusting suitably incoherent pump rate,the atomic injection ratio and the exit rate. The curves of the linear gain and the nonlinear gain were similar with the Rabi frequencies of the driving fields. The curves of the linear population difference and the nonlinear population difference were similar too. The linear stable value of the gain was larger than the nonlinear stable value of the gain.

High power double-clad fiber lasers under multi-point pumping facilitate the increasing of the power and optimizing of the output performance. The forward and backward pump mode is calculated respectively. The calculated results show that pump power reflectivity at the end of the cavity affects the output performance and the optimal fiber length apparently. The relation of the number of pump point and the output power is obtained from the numerical modeling,furthermore,the optimal fiber length as a function of pump point is obtained. The conclusion can be used as reference for the design of the double-clad fiber laser configuration under multi-point pumping.

To simplify the structure of the polarized CO2 waveguide laser and its manufacture technology,a type of the polarized CO22 waveguide laser with new polarization device was presented. This new polarization device is a rectangular waveguide cathode in fact. By utilizing the special action of the device at the mouth of discharge waveguide to the light beam in the resonator,only the light beam with the polarization of electric field in one direction can oscillate,and the polarized light can be exported steadily. The polarizing mechanism of the laser was analyzed theoretically,and the linear polarization degree of the output light was measured experimentally. The new laser,with over 98% linear polarization degree of output light,has characteristics of simple structure,low price,and so on.

Traditionally,the quantization scheme for a mesoscopic LC circuit lies in that electric charge q and electric current L×I are respectively quantized as the coordinate operator Q and momentum operator P. A new quantization scheme is proposed in which number n of the electric charge q(q = en)is quantized as the charge number operator and the relation between electric current and phase operator θ can be derived,in this way the quantization of mesoscopic LC circuit in the context of number-phase is realized and the corresponding Hamiltonian is obtained. The results show that the Cooper pair number-phase-difference quantization scheme is also available for Josephson junction after introducing the entangled state representation.

Considering two two-level atoms initially in the non-maximally entangled state,one of them is put into an initially empty cavity and resonant interaction occurs. It is shown that the emission properties of the atom inside the cavity will be affected when the other atom outside the cavity is manipulated. And the degree of entanglement of the atoms can also affect the emission properties. This conclusion is generalized to the situation of the two-mode squeezed property of two cavities interacting with three two-level atoms.

Xi Yongjun et al proposed a scheme of probabilistic teleportation of an arbitrary three particle entangled state via three pair nonmaximally entangled particles. In this scheme,receiver need use auxiliary particles to realize the teleportation. Not using two auxiliary particles,the system state is linear combination of Bell bases and transformation operator. If transformation operators have inverse operators,the teleportation can be realized by performing a inverse transformation. The relation of the determinant of transformation operators with entanglement measure is obtained.

The reflective and transmissive phase shifts of photonic crystal Bragg mirror is studied,and the revelation is the reflective and transmissive phases all increase when the incident light frequency increases. In the vicinity of central frequency the phase shifts are linearly related to frequency. By applying the first order approximation of Taylor expansion the formulae of reflective and transmissive phase shifts are obtained in the vicinity of central frequency,and the change characteristics of phase shifts are well described. The characteristics of the resonant mode frequency of Bragg microcavity varying with the microcavity thickness is also studied,furthermore the resonant mode frequency is obtained as the first order approximation in the vicinity of central frequency.

Based on chaotic parameter modulation,an M-ary digital communication scheme(CPSM)is designed and realized. The performance of the binary and quaternary digital spreading spectrum communication systems by using different chaotic carriers and spread factors is studied,and those factors affecting systematic performance are also analyzed. The results by computer simulation indicate that the performance of the systems can be improved by enlarging spread factor. In addition,these proposed systems are of good noise immunity,easily to implement.

The time-dependent Schr?dinger equation of realistic hydrogen atom in intense laser field and static electric field is solved by split-operator method,and the abnormal behaviors of high-order harmonic generation(HHG)in intense laser field is investigated,which is caused by a static electric field. Our study indicates that intensity of odd-order harmonic generation decreases,even-order harmonic generation appears and the HHG spectrum exhibits a doubleplateau structure in the presence of a static electric field. By using wavelet transform,the emission of HHG in different time is obtained. And by means of semiclassical theory,the changes of HHG for realistic hydrogen atom in the static electric field is explained.

Based on the current counter-jamming situation of laser terminal guidance weapon,the high-repeated frequency jamming is analyzed,and the scheme of counter high-repeated laser active jamming is put forward. By analyzing the math model and concluding its principle,the period of high-repeated frequency is calculated. This principle is the core of the scheme,key points of which are the calculation of the period of high-repeated frequency signals and the determination of the synchronous point of the inverted high pulse repetition frequency signals.The scheme can solve the problem of the active jamming. The scheme and a new kind scheme of laser code which we have put forward compose the integrated scheme of counter laser active jamming to the laser terminal guidance weapon.

In explosive experimentation,the collimator of conventional all fiber velocity interferometer can't availably collect diffuse reflection of high-speed object. With the superluminescent diode instead of the light source of conventional all fiber velocity interferometer,feasibility of all multi-mode fiber velocity interferometer is elementarily validated. The principle and the structure of all multi-mode fiber velocity interferometer are put forward and described. At last,comparing all multi-model fiber velocity interferometer with conventional all fiber velocity interferometer in experimentation of velocity measurement for speaker,the same result is acquired. It shows that the new interferometer can successfully probe the velocity profiles.

Based on classical electromagnetic theory,the conservation law for linear momentum in an optical field is derived. The expressions of gradient and scattering forces exerted on an arbitrary object are obtained. It validates that electromagnetic model can be used to explain fundamental of laser trapping and manipulation of living biological cells and organelles with cells. Theoretical analysis indicates that the forces acting on Rayleigh particles can be divided into two types: the scattering force which comes from electromagnetic wave momentum changes due to the scattering by a dipole and the gradient force which is equal to the Lorenz force acting on the induced dipole. And the optical forces are relative to systemic parameters including the radius of the beam waist,the relative refractive index of particle and surrounding medium,the radius of particle and laser power.

Usual interaction potential is the squared potential well to describe the motion behaviour of a hole in the single quantum well. The new interaction potential with ch－2x form is assumed. In the frame of quantum mechanics,Schr?dinger equation to describe the particle motion is reduced to the hypergeometric equatin by this potential. The eigenvalue and the eigefunction problem of the Schr?dinger equation are transformed to the eigenvalue and the eigefunction problem of the hypergeometric equation. The eigenvalue and the eigefunction of the system are calculated,and the distribution and number of level in quantum well are discussed. As example,the level and the transition of a hole in the single quantum well for material Ga1-xAlxAs-GaAs-Ga1-xAlxAs are calculated. It shows that coincidence between the theory and the experiment is improved futher.

The I-V characteristics of the long-wavelength infrared HgCdTe photovoltaic devices fabricated by different process including standard process,reflowing process and post implantation annealing process were measured and investigated by model fitting analysis. This model includes four current components,such as diffusion current,generation-recombination current,band-to-band tunneling current and trap-assistant tunneling current. From the model fitting analysis,the trap concentration increased dominantly during the reflowing process,which led the the trap-assistant tunneling current and the g-r current increased largely. The reverse bias resistance dropped a lot and the performance of the device degraded. Compared to the performance of the post-implantation annealed device,it is presumed that the reason which led to the degradation of the performance of the reflowed device is the instability of the ZnS passivation layer.

A method for all-optical frequency multiplication/recovery based on the semicon-ductor optical amplifier(SOA)ring cavity with the interference is proposed and demonstrated by numerical simulation. This technique can be used to generate low clock amplitude jitter and input polarization independent pulse trains with the repetition rates of 5～25 GHz from 2.5 GHz driving pulse. Bias current of SOA effect on the amplitude of the output pulse train is great,and there is an optimized bias current of SOA for the base frequency of the 2.5 GHz and 10 GHz,respectively. In addition,this scheme can be applied to the extraction of the clock signal from a pseudorandom bit sequence signal.

The main method to enhance the system capacity of OCDMA networks is coding user's data in both time and spectral domains. Based on the 1-D optical code-pattern and code-hoop,a new geometrical device is designed,called optical code-cylinder,to denote the wavelength-time 2-D optical signature codes,from which the scheme of correlation checking of 2-D signature code family is given. Then based on the optical code-cylinder,the analytical theory of maximum system capacity of 2-D OCDMA system is established in detail. The results from code-cylinder are concordant with thoses of Johnson bound of correcting code.So,the code-cylinder method is useful and convenient tool for the performance analysis of 2-D signature code.

Considering the influence of high-order dispersion and high-order nonlinearity on quasi-soliton transmission,the effects of third-order dispersion,self-steepening and ISRS are investigated by numerical simulation. The result indicates that among these three effects,the influence of the ISRS effect on quasi-soliton transmission in the actual fiber is primary. Under the influences of these effects,the width of quasi-soliton broadens,the peak value of the pulse descends and the shape of the pulse cannot keep as the original shape.

A novel Er3+-doped tellurite glass with compositions of TeO2-ZnO-Na2O-Bi2O3 was prepared,and the intensity parameters,spontaneous emission probability,absorption and emission cross-section of Er3+ ions were calculated according to the Judd-Ofelt and McCumber theory. The signal gain characteristics of fiber amplifier with this erbium-doped tellurite glass fiber as a gain media were investigated based on a four-level population rate-light power propagation equation model pumped at wavelength of 1480 nm,in which energy up-conversion,cross relaxation,excited state absorption and amplified spontaneous emission noise of Er3+ions were considered. It is shown that the tellurite glass fiber prepared here presents a bigger signal gain and wider gain spectrum,its maximum signal gain and gain width at 20 dB exceeds 40 dB and 80 nm respectively,and its gain spectrum can across the C+L band region when pumped at 200 mW and injected with-30 dBm×56channels signal. The results indicate that the erbium-doped tellurite glass is a kind of better gain media which can be applied to broadband amplifiers. Moreover,the fiber structural parameters such as fiber length,fiber radius and relative index difference will have much affects on its gain characteristics.

The evolution equations for the parameters of the optical Gaussian-shaped pulse in optical fibers are derived by means of variational method from the MNLS equation. Then three restricted relations between amplitude and width,frequency and chirp,width and chirp are derived. Analytical solution about the width of pulse evolves on the propagation distance is obtained. The influence of the fifth-order nonlinearity on the propagation properties of Gaussian-shaped pulses in optical fibers is discussed. And the profiles of the evolution for the fifth-order nonlinearity(r),chirp(b),initial chirp(b0),distance(Z)of the frequency band width(a)are drawn.

Image transmission through an equilateral triangle waveguide is discussed theoretically. Self-image period in a mental equilateral triangle waveguide is derived;and image transmission on the waveguide is studied by numerical simulation. With the help of numerically analyzing,it is found that three output images form from one of three the self-imaging length of the waveguide,moreover,the symmetrical output images rotate 120°angles.

Automatic switched optical network(ASON)is a set of optical infrastructure with high flexibility and extensibility,which can provide service at optical layer directly and can fulfill the requirements of subscribers,so it can solve some network problems perfectly,such as extensibility,manageability,subscriber bandwidth distribution and end-to-end network protection. We proposes the architecture of ASON wicth including three planes,three interfaces and three connections,then analyzes the networking mode and networking structure. In conclusion,we introduce the ASON networking scheme of Lucent.

Multilayer recovery independent and interworking,and multilayer recovery of GMPLS-based intelligent optical network(ION)are analyzed. We can conclude that ION can provide rapid and efficient survivability.

Based on the study of CWDM and wavelength conversion technology,OTU module applicable to CWDM system is designed. The module supports an eight-channel of CWDM and works in a state of multi-rate. The module has 3R function to ensure the quality of the signal conversion,and high speed data and clock signal are output and can be used as performance monitoring. Experimental results show that the module successfully realizes the conversion of wavelength with better stability and practicability.

The driving scheme is one of key factors to improve the performance of OLED,which is made of luminescence material AND with the NPB adulterated. After applying reversed-bias on it and studying its characters,we find the stability of OLED is enhanced greatly. By DC driving and AC driving on the same kind of OLED respectively,the results show the lifetime of OLED in AC driving model is much longer than OLED in the DC's.

The conceptions in microwave engineering are used to modeling the light transmission process in fiber Bragg gratings,yielding the corresponding transfer matrix in the microwave network grating model. The relationship of this novel transfer matrix and the traditional transfer matrix in piecewise uniform grating model is clarified. Combining the modified effective index method,a novel method for calculating the complex reflection spectrum is proposed. The MT matrix in this method is concise and a good exactitude of this method is confirmed by numerical simulation.