The relationship between fluorescence lifetime and OH groups concentrations in theN2122andN3122phosphate laser glass used in the Shenguan Facility is investigated experimentally. We also study experimentally and theoretically the influence of fluorescence lifetime and loss on gain property in phosphate glass. It is shown that to increase fluorescence lifetime of glass can effectively improve the gain property. When fluorescence lifetime of glass adds 10 percent, its gain coefficient will increase 5 percent. We also measured the gain of two groups glasses (4 samples) with different fluorescence lifetime and loss under the same pump condition. The results indicate that in case of keeping the gain property unchanged, we can increase its fluorescence lifetime and reduce its loss requirement.

Abstract We have measured the X-ray angular distribution (dE/dΩ) and X-ray conversion (ηx) from a disk targets (Φ600μm×4μm) irradiated by 0.35 μm laser (<100 J) with soft X-ray flat-response detector.dE/dΩ=a+bcosθis independent ofangles.ηxdecreaseds with the increasing laser incident angles with respect to the target normal.ηxalso decreaseds when Au disk is replaced by multilayer film (0.11μm)+Au disk or CHfilm (0.4μm)+Au disk.

The growth mechanism of proton exchanged waveguides was studied, and the formula for calculating the depth of the waveguides was deduced.

A new phase unwrapping technique in Fourier transform profilometry (FTP) is proposed. The technique is based on digital weightd filter and modulation analysis to from reliability mask. Phase unwrapping is then fulfilled in order of reliability function. This technique considers both accuracy and reliability. Experimental result of complex object shape measurement is given.

The application of wavelet multiscale edges detection method in the fluorescence lifetime imaging microscopy is studied. A Fluorescence lifetime image is analyzed, and the results show that this method is very effective.

The principle of the time integrating acousto optic correlator is analyzed theoretically. The correlating peak overlapped on a vias was detected experimentally. To modify the correlating peak, the post processing circuit was introduced. The ideal correlating peak was obtained.

Germanium nanocrystals embedded in SiO 2 glassy matrix have been prepared on glass substrates and Si(100) wafers by r.f. cosputtering and post annealing methods. Raman scattering spectra at various annealing temperature were measured. Compared with bulk Ge, a red shift and broadening of Raman scattering spectra were observed. According to the parameters of Raman scattering spectra, we calculated the average crystal size of nc Ge. The experimental results are in agreement with the phonon confinement theory.

A diode pumped single frequency intracavity doubled CW laser has been demonstrated by optimizing several spectroscopic parameters and cavity length with precise temperature controlling of the Nd:YVO 4, KTP and diode laser. Stable single mode output power of 7.5 mW for the green light was obtained when the incident pump power was 430 mW which is 13 times greater than the threshold.

The single pass gain of the chirped pulse in Ti:sapphire regenerative amplifier changes with radius of the pumping beam or radius of the signal beam. With different pumping energy of frequence doubled Q switched Nd:YAG laser, we measured the building up time and output energy when the regenerative amplifier is seeded or not seeded. The energy gain of 2×10 7 is obtained.

We reported the experiment result of laser output at 1.57 μm on Nd:YAG 1.06 μm laser using the OPO method and taking the stimulated Brillouin scattering (SBS) backward amplified output as pump source. The maximum output energy was 21.6 mJ, and the corresponding conversion efficiency is 32 percent. Comparaed with the result directly pumped by Nd:YAG 1.06 μm laser, the efficiency is increased by 1.9 times and the threshold is reduced by 1.7 times. The experimental result is in good agreement with the theoretical analysis.

The Q switching characteristics of Cr 4+ :YAG crystal are studied theoretically and experimentally. The pulse energies and pulse widths of a Cr 4+ :YAG Q switched Nd 3+ :YAG laser in different conditions are measured. And the experimental results show good agreement with the theoretical predictions of energy and rough agreement with the theoretical predictions of pulse width. The other phenomena of the Cr 4+ :YAG Q switched Nd 3+ :YAG laser are also qualitatively analyzed.

Integration calculations for the absorption spectrum of PPQ polymeric cast film, by means of the Kramers Kronig relation, were performed for a serial number of wavelengths. An existence of an region of anomalous group velocity dispersion (GVD) span near (550￣700) nm band was evidently indicated. The dispersion parameter β 2 is relatively small, |β 2|<1.2 ps 2/m, so that a dispersion neglected nonlinear Schordinger equation was used to described the propagating behavior of femtosecond colliding pulse mode locking (CPM) laser pulses in planar optical waveguide of PPQ film, and consequently, the obtained nonlinear refractive index coefficient n 2 was in a good agreement with the reported value.

The visible region absorption spectra and photoluminescence spectra excited by 514.5 nm and 488.0 nm laser for the sesquioxides of the rare earths Y 2O 3, La 2O 3 and Lu 2O 3, which were finely divided powders of spectrographic purity, have been measured. When 488.0 nm and 514.5 nm laser lines were used as pumping excitations, the luminescence was abserved from Y 2O 3 and Lu 2O 3, whereas the sample La 2O 3′s fluorescence was only excited by 488.0 nm laser line. Comparing the asorption spectra and photoluminescence spectra of them with that of other RE 2O 3, the results show that the luminescences of Y 2O 3, La 2O 3 and Lu 2O 3 arised from the sample′s trace impurity Er 3+ , Sm 3+ and Eu 3+ respectively.

The wideband Raman amplification with unfocused tilted pumping beam is studied. The effects of Raman gas pressure and pumping angle on the Raman energy amplification are given. The limitation of bandwidth in Raman amplifier for high power excimer laser system is discussed.

A novel method is presented to control the optimum input polarization of the interferometric fiber optic sensor arrays by the sum of each sensor′s feedback signal. The minimum visibility of the element in the array under control is calculated, and the probability to reach this situation is estimated. The analyses show that the method is both simple and feasible. Each sensor′s visibility can approach to 1 by signal process, which eliminates the polarization induced fading in each sensor of the array.

Reflection induced phase retardation (RPR) on light turning points of bulk glass optic current sensors would influence the immunity to electromagnetic interference of the sensors. The theoretic analysis, results of numerical simulation and experiments are presented.

A theoretical study of the mode difference between the left and right elliptically polarized light in the differential laser gyro is presented. This differences is critical for the differential laser gyro operation and it is caused by the S P phase and Q anisotropy of the ring cavity.

How to lengthen the span of smplifiers is a crucial issue in use soliton transmission system. Based on theoretical analysis and computer stimulation, it is proved that the ideal distributed Er 3+ doped fiber amplifier can improve the noise performance and lengthen the span between two pumping stations. A preliminary discussion about the result is presented.

A theoretical treatment and a new effective numerical method are proposed to reconstruct the depth distribution of optical absorption coefficient in multilayer inhomogeneous material by the optical and thermal signals, which are related to the surface temperature of the sample measured with the optical and thermal method. Numerical simulations demonstrate the performance of the approach is better.

The coupling efficiency between the waveguide and detector absorber layer is duscussed on the basis of the geometric optics method. The dependence of the coupling efficiency on the refractive index distribution and length of absorption region in the vertically coupling structure is analysed.

The formulas of populations distribution and Doppler cooling force dependent on the velocity of atoms were described by considering the physical model of one dimensional σ + σ - cooling and repumping lights acting on 24 sub level of Sodium atoms. The velocity dependent Doppler force and P(v) were calculated and discussed at the conditions of different detunings of cooling light, different intensities and detunings of repumping lights. The results of calculations based on this model can interpret the experimental phenomena in magnetic optical trap and can be used as reference for selecting the parameters in experiment.

The model for describing the atom cavity field interaction including Kerr effect and Stark effect is studied. The two effects only influence the detuning which depends on a conservative operator of the system. Under certain conditions, the two effects have the same influences on the atom field interaction. The antibunching effect of the field is discussed when the initial field is in a macroscopic quantum superposition states. We also investigated how to obtain the solution of atom field interaction in a generalized Kerr medium.

The characterization of femtosecond optical pulses for Ti:sapphire laser output is conducted with two photon induced transitions in blue light emitting diodes. Excellent phase relationship between the two separated pulses are recorded from the fringes of the two photon induced, second order correlation function. It is demonstrated that the two-photon induced current can greatly simplify the femtosecond pulse characterization by direct converting the photon signal to current signal.

Absorption and scattering properties of monoenergetic X rays of 30 keV-110 keV in iron have been studied with Monte Carlo method. The angular distributions of scattered photons and the spectra of backscattered radiation are presented. The results show that the backscattered radiation is primarily the characteristic X radiation of iron for the incident X rays of low energy, and that with the energy of incident X rays increasing, the backscattered radiation of high energy increases and the characteristic X radiation decreases rapidly.