Current trends of development about complex-period photonic crystal were reviewed. Multi-layer complex structure and nesting complex structure in one-,two-,and threedimension were compared. It can be concluded that the complex structure can produce more photonic bands than single structure. The multi-layer complex structure can adjust the wavelength and width of photonic band,and the nesting complex structure can control the model of band. The preparation and usage of complex structures were also introduced.

Since the efficiency and stability still need to be enhanced,FOLED(flexible organic light emitting device)is still not mature enough to be commercialized. This article provides a review of the technologies of FOLED including selection and treatment of flexible substrates,selection and design of anode,encapsulation of the FOLED,introduces the research progress of several key technologies of FOLED,and also makes a prediction of its future market.

The basic concepts of fractal geometry and fractal box counting dimension are introduced. A new method of recognition of terahertz spectrum is suggested based on these concepts. The terahertz spectrums of two Chinese traditional medicines are obtained and their box counting dimensions are given and compared. The different medicines can be identified well in this way.

The processes of multiphoton ionization(MPI)dissociation of 1,3-dibromobenzene was studied at 266 nm. The time of flight mass spectra of 1,3-dibromobenzene were obtained.We measured the percentage of fragment ions to the total ion current and the dependence on laser intensity of the molecule. Based on the experimental results,the multiphoton ionization-fragmentation(MPIF)mechanism of 1,3-dibromobenzene was discussed. The conclusion is that the primary channel is multiphoton dissociation of parent molecule and multiphoton ionization of neutral fragment. Some formation channels of the small fragment cations were analyzed,i.e. C6H(+,4),C5H(+,3),C4H(+,2),C3H+ etc. and most of ion fragments are produced by ion-fragment dissociation staircase.

Using the CW laser absorption and fluorescence method,the cross sections for the fine structure mixing and quenching of the Cs(6P)state,induced by collision with Ne atoms,were measured. Cesium atoms were optically excited to the 6P3/2 state. The excited atom density and spatial distribution were mapped by monitoring the absorption of a counterpropagating single mode laser beam,tuned to the 6PJ →8S1/2 transitions. The effective radiative rates were calculated for the 6PJ → 6S transitions. The fluorescence intensity I895 of the sensitized 6P1/2 →6S1/2 emission was measured as a function of Ne density in the range 0.5 × 1018 ＜ N ＜4 × 1018 cm－3 at constant temperature T=337 K. It was found that the quantity N/I895 exhibited a parabolic dependence on N,confirming that the quenching of the 6PJ states is due to collision with Ne atoms,not with Cs ground state atoms. The. coefficients of the second-order polynomial fitted through the measured data yielded the cross sections σ21 =(1.90± 0.82)x 10-19 cm2 and σD =(8.97±3.85)× 10－19 cm2 for the 6PJ fine-structure mixing and quenching,respectively,due to collision with Ne atoms.

A physical model was established to study the distribution and change of temperature field of Nd∶ GGG disc operated under heat-capacity mode. By using heat conducting equation and Green function,the expressions of temperature field inside the crystal were obtained during the operation and cooling period of the laser;the obtained data reflect the change of temperature filed. The temperature field was calculated after the crystal was pumped as long as 4 s under the pump conditions(rectangular LD facula 3 cm,power 8.1 kW,frequency 500 Hz,width 0.2 ms),and the maximal stress is up to 47% of the crystal rupture limit at the end of 4 s. The cooling time is about 60～70 s when the back of the disc is cooled at the temperature 280 K and 290 K respectively;the cooling time is shorted to be about 30 s when both the back and side of disc were cooled at the temperature 280 K.

With adaptive feedback system based on Genetic Algorithm(GA),selective excitation of coherent anti-Stokes Raman scattering for dibromomethane was successfully achieved. The optimal pulses were characterized with second harmonic generation frequency-resolved optical gating(SHG-FROG)and displayed as trains of sub-pulses with negative chirp. This experimental demonstration of selective excitation between neighboring levels indicates that coherent control has a great potential in the improvement of sensitivity and is a meaningful method in the complex molecular system.

The entanglement purification protocol for the system of atom interacting with two distinct optical cavities is discussed. The fidelities before and after the system purification are studied. The results indicate that the effect of the phase decoherence rate and detuning parameter on the fidelity can be reduced by modifying two quantum logical gates. Then,maximal fidelity of quantum teleportation can be achieved.

Analysis indicates the importance of precise temperature control of single-photon detector used for quantum key distribution in infrared communication wavelengths. There exists an optimal operation temperature to satisfy the highest detection efficiency with the lowest dark counts and the dark counts are sensitive to the temperature. Precise temperature control based on ADN8831 is achieved for single-photon detector. The characteristics and applied circuit of the chip ADN8831 are presented in detail. The precision of the controlled temperature is 0.01℃. Photocurrent-Voltage and Dark-current-Voltage characteristics measured at different temperatures are presented.

Multi-channel scan radiometer(MCSR)on FY-2C Satellite launched in October,2004 has been working in orbit for two years. In order to improve quantitative application and track long-term changes in the visible channel,an onboard calibrator using a small beam of sunlight as source is designed,which is fixed on the second mirror and made up of two plates,two prisms and a set of baffles. The calibrator including optical structures,ground-based tests and on-orbit parameters are concisely described. In pre-launch experiments a mirror is used to lead the sunbeam into the MCSR,but in-flight performances the instrument can get the sun signal every midnight. By analyzing and comparing the signals and images,differences between them can be corrected,channel performances such as attenuation can be acquired in time and data also can contribute to better calibration results.

Dual rotating retarder configuration is applied in measurement system,whose incident and scattering light are modulated by synchronously rotating two quarter waveplates. From the 25 Fourier coefficients measured by performing Fourier decomposition of the signal,the 16 elements of sample's Mueller matrix are determined. We compare the experiment data of air with the ideal matrix to check the accuracy of measurement system,and present the standard error of each Mueller matrix element. Finally,the depolarization of polytetrafluoroethylene sample is analyzed quantitatively by the measured Mueller matrix.

Based on a spherical shell structure and the graded finite potential well model,shifts of bound states caused by the interface effects on the binding energy level of hydrogenic impurities in a weakly-confined spherical semiconductor quantum dot heterostructures are studied. It is found that the interface effects are fairly significant when the shell thickness of the quantum dot is less than or equal to 10 nm. The interface effects become weaker when the thickness of the heterostructures increass,and the ground state energies gradually decrease. Finally the ground state energies corresponding to different values when Aity function becomes zero tend to be a fixed value,then the interface effects can be ignored.

Extensive application of GaN-based blue LED is greatly affected by increase in light-extraction efficiency. Refraction index of Ohmic contact to p-type GaN developed by oxidizing Ni/Au thin films is calculated. Power flow propagation within the p-contact is analyzed and coupling layer with proper refraction index over the p-contact is design to reduce light-absorption and reflection by p-contact. Frustum of cone structure scheme of ITO layer is applied to attenuating total reflectance(ATR)of the interface between air and ITO so that light-extraction efficiency of GaN-based LED can be increased. Result calculated by transfer matrix method shows that transmissivity of coupling layer/p-contact films at 450 nm wavelength increases to 75% for the ITO coupling layer with optical thickness of π/2 and refraction index of 2.02.

At high bit rates fiber transmission systems,polarization mode dispersion(PMD)is considered as the ultimate limiting factor for transmission of information. The pulse root mean square broadening is a main physical variable to judge signal transmission performance. We derive the broadening effects induced by the PMD,and give the exact analytical expressions for the expected pulse broadening in a fiber-optic transmission system suffering from firstorder polarization mode dispersion(PMD). Furthermore,we use the result to calculate the Gaussian pulse.

In optical networks,the quality of service(QoS)is degraded by signal impairments incurred by non-ideal transmission. At the same time,different classes of service in the current optical network have different QoS requirement. So it is essential to develop intelligent routing and wavelength assignment(RWA)algorithms to combat the effects of impairments according to different QoS requirements. A new RWA algorithm is presented by combining the above two issues together. The simulation shows that the new algorithm can insure QoS of provisioned connections for clients with different QoS requirements.

The p-type Ohmic contact of Ti/Al/Au multiple metal alloy for 4H-SiC avalanche photodetector(APD)was investigated and the lowest specific contact resistance of 5.4×1O－4 ΩC cm2 was achieved by the linear transmission line method(LTLM). The scanning electron microscope(SEM),Auger electron spectroscopy(AES),X-ray photoelectron spectroscopy(XPS)and Panalytical X'pert PRO X-ray diffraction(XRD)were measured to analyze the contact morphology,chemical composition and the phase formation of the samples before and after annealing. In addition,the electrical properties of 4H-SiC APDs with the same p-type Ohmic contact were also measured. Near the breakdown voltage of about－55V,the voltage descent at p electrode was as low as 0.82 mV,which showed that the Ohmic contact can satisfy the requirement of 4H-SiC APD.

The optical properties and electronic structures of one mono-substituted polyacetylene and two di-substituted polyacetylenes have been investigated. Each of the substituted polyacetylenes bears a carbazole unit in the side chain. In spite of the differences in their molecular structures,the dilute solutions(～1 × 10－6 M)of these substituted polyacetylenes exhibit the same absorptions and the same deep-blue emissions(～360 nm). Interestingly,the absorption and emission spectra of these substituted polyacetylenes are similar to those of the small molecule carbazole. As the concentration of the substituted polyacetylenes increases to about 1 × 10－3 M,we have detected intense blue emissions at about 475 nm. Using Huckel tight binding programs,we have calculated the electronic structures of the carbazole-containing polyacetylenes. Our results indicate that the absorption,the deep-blue emission(～360 nm)and the intense blue emission(～475 nm)originate from the carbazole chromophores in the side chain.

As a key subsystem of AMS-02(Alpha magnetic spectrometer),tracker thermal control system(TTCS)is developed to transport heat dissipated by the silicon tracker electronics to radiators that radiate the heat to deep space and to keep the temperature of the silicon tracker invariable. To enhance the reliability,a hierarchical monitoring strategy is implemented in the electronic subsystem of TTCS to monitor the system working status. The general architecture and components of TTCS are presented at first. Then the hardware structure of the monitoring system is described briefly. And the hierarchical monitoring model is designed and analyzed in detail,in which the FPGA-implemented health-guard strategy further improves the safety of the TTCS. Lastly,based on the ESTP(earth simulation testing platform)system,test methods and results are given to show the reliable operation of TTCS. This strategy has been implemented successfully in prototype design.

Stimulated Raman scattering is one of the main restriction for the improvement of high power fiber laser. The Raman effect in high power fiber laser is studied through numerical simulation. The results show that SRS can be suppressed effectively by increasing signal wavelength and reducing reflectivity. Also,the Raman characteristics with different pump modes are discussed. For the first time,the Raman effect in high power fiber laser under multi-point pump is studied. The conclusion is useful for the optimizatin of high power double-clad fiber laser.

A large mode area core erbium doped K9-glass single-mode photonic crystal fiber is designed by getting the pump and signal intensity profiles from plane wave expansion method(PWEM)and solving propagation-rate equations. Its diameter is 20μm,limit ellipticity error is 94.7%,and limit offset of inner ventage is 0.1 μm. Then we analyze its amplifier characteristics. From numerical analysis when concentration of the erbium ions(Nt)is 1×1026,we get the threshold of this fiber amplifier is 180 mW,and the optimal length is 0.26 m.

Potonic crystal fiber is widely applied in the active and passive devices of the fiber communication systems and the photoelectric signal detection. The air hole refractive index is analysed by Edlen formula. And the distribution of the quartz thermal stress and the refractive index is analysed by the heat conduction model in the solid-core photonic crystal fibers in the temperature field. The fluctuation of the pulse phase and mode birefringence in the photonic crystal fibers is also discussed. Optical pulse in the photonic crystal fibers is less sensitive to the tomperature than in general single-mode fibers. So it is beneficial in the active and passive devices in the photoelectric signal detection.