A U_qp(u_1,1) model is presented for describing vibrational spectra of diatomic molecules. The model is tested on the vibrational spectra in the X¹Σ _g⁺ state of H₂ obtained through the Rydberg-Klein-Rees method.

The Boltzmann-Nordheim-Vlasov (BNV) model was employed to investigate the giant monopole resonance (GMR) built on very excited residula nuclei formed in heavy-ion collisions. Roughly speaking the GMR energy of BNV model is very similar to the value given by the empirical formual E_GMR = 31.2A^-l/3 + 20.6A^-l/6 and hardly changes with impact parameter and bombarding energy.

Excitation functions of the dissipative products in the reaction ¹⁹F+⁵¹V have been measured from 102.25 to 109.50MeV by 250keV steps at θ_l = 21.7°, 36.1°and 40.5°. The rotation angular velocities ω and the energy coherence widths Γ of the corresponding dinuclear systems were extracted. The coherence rotation and its importance in the reaction process have been discussed.

The pion and kaon production in heavy-ion reactions at 1GeV/nucleon has been investigated in the relativistic Vlasor-Uehling-Uhlenbeck model, which has been generalized to include the effect of nuclear medium on kaon and pion. The calculated results show that the attractive pion optical potential not only enhances apparently the yield of pions with low transverse momenta, leading to a reasonable fit to the experimental data, but also increases the kaon abundance.

We report the generation of intensity squeezing in a single-mode laser diode by weak external cavity feedback. The measurable squeezing of the output beam is 4.7%, corrected to 8.9% for the actual squeezing. This proves that intensity squeezing can be obtained by weak feedback.

To our knowledge, we have demonstrated for the first time that (2+1)-dimension photorefractive waveguides can be written and stored by light using the (2+1)-dimension photovoltaic dark spatial solitons in LiNbO₃:Fe crystals. It can guide a probe beam of the same wavelength as that of the writing beam.

Using the Cerenkov second harmonic generation, 478 nm blue and 402nm violet light are generated by direct frequency doubling of 956 and 804 nm diode lasers in a same proton exchanged MgO:LiNbO₃ waveguide. Under the low fundamental guide wave power of less than 1mW, the estimated value of the output blue and violet light power is in the order of 0.1-0.01μW.

A technique for chirped-period fiber gratings with etching method is reported. An analysis is presented for the behavior of the chirped gratings as a function of wavelength, the angle between the illuminating beams, as well as the position of the gratings. Experimentally, chirped fiber gratings have been etched on the D-fiber. Results obtained are in good agreement with theoretical analysis.

The self-generated magnetic field induced by an ultraintense short laser pulse propagating in a uniform underdense plasma is investigated. The magnetic fields are strong and associated with the plasma wave wake field. Some properties of dc magnetic field in two extreme laser pulse regime are described.

The effects of low energy electrons in scanning tunnelling microscope operations are explored, with the emphasis on its role in the fabrication processes. A simple model based on the continuum electron diffusion is proposed to account for the observed sub-surface characteristics of the nanoscale features. The results suggest that the local transport properties could affect the outcome of such operations.

Under very low pressure (0.1 Torr) the high density nucleation of diamond on mirror-smooth silicon in hot filament-chemical vapor deposition system was obtained. The nucleation density of order of 10¹⁰-10¹¹cm^-2 was achieved, the same achievement which obtained in microwave plasma-chemical vapor deposition system with negative bias. In this paper the nucleation technique and the effect of low pressure on diamond nucleation were discussed in detail based on the molecular dynamics.

The preparation procedure, the transmissivity, and the two-wave coupling properties of coppermodified potassium sodium strontium barium niobate (KNSBN) crystals are reported. The Cu ions doped in KNSBN can form two deep energy levels. This means that they are able to act as centers for free charge carrier stimulation and recombination. The two-wave coupling gain coefficient of KNSBN: Cu is two times larger than that of KNSBN. The photorefractive sensitivity of KNSBN: Cu is estimated to be in the order of 10^-3cm²/J.

Optical analyzer technique are used to measure the sound speed as a function of pressure for shocked multiphase alloy 93 W containing 93%W, with 4.2%Ni-2.45%Fe-0.35%Co alloy as binder, all in wt.%. Below 250 GPa, the speed increases with pressure, then a bulk“softening” process occurs at 250 to 340 GPa, afterwards the speed again rises with pressure and coincides with the calculated bulk sound speed, showing a fluid-like behavior for this alloy. Lindemann melting law calculations were made for both the binder and the tungsten. The results showed that 250 GPa corresponds approximately to the pressure for the binder beginning to melt, and 340GPa corresponds to that for tungsten. Therefore, we believe that the shock-induced “softening” mechanism for this kind of multiphase alloys can be attributed to the binder melting.

Raman scattering from Zn fine spheric particles coated with ZnO of variable thickness is measured, and a broad line can be found. The Raman line shifts to lower frequency side with the increase of oxide thickness. A theoretical analysis based on the existence of surface phonon mode has been made. Agreement between experiment and theory is good.

The dependence of optical interface phonon on structure was demonstrated for thin layer inserted GaAlAs quantum well structures. It was found that the dispersion is sensitive to the Al-content of the inserted layer but almost independent of the position of the layer. The results showed that phonon modes can be modulated by adjusting the well parameters, which is useful for some device applications.

A new Ag rough film system, deposited on silicone oil surfaces by rf-magnetron sputtering method, has been fabricated. The chrysanthemum-like surface morphology at micron length scale is observed. It is proposed that the anomalous critical behavior mainly results from the relative shift between the Ag atom clusters and the substrate. The discussion of the deposition mechanism is also presented.

BaTiO₃(BTO)/YBa₂Cu₃O₇ (YBCO) heteroepitaxial films have been fabricated on (100) SrTiO₃ substrates by pulsed laser ablation. X-ray characterizations show the BTO/YBCO bilayer films have a highly epitaxial nature. Rocking curves for the BTO (002) and YBCO (005) peaks have full width at half maximum values of 0.36°and 0.32°, respectively. The Ф scan plots indicate good in-plane alignments of these epitaxial films. The ferroelectric properties of the B TO/YBCO heteroepitaxial films were evaluated by capacitance-voltage measurement in metal-ferroelectric-metal configuration.

High quality diamond epitaxial film has been obtained on high pressure synthesized cubic boron nitride crystal surface by dc glow discharge chemical vapor deposition. The growth characteristics of the epitaxial film have been investigated by scanning electron microscope. The quality of the film has been confirmed by Raman spectroscope to be close to that of natural diamond.

CN_x films prepared by high dose ion implantation and post-annealing were studied by Auger electron spectroscopy, x-ray photoelectron spectroscopy and x-ray diffraction. A nearly uniform CN_x layer was formed. Carbon and nitrogen were found covalently bonded in the films. X-ray diffraction results showed that two crystal phases of C₃N₄, β-C₃N₄ and p-C₃N₄, have been formed in the matrix of carbon.

By using an ab initio calculation, it is found that the variation of the fundamental band gap of (α-GaN)_n / (α-AlN))_n (0001) superlattices is remarkably different from that of (β-GaN))_n / (β- A1N))_n (001) superlattices. The difference in band gap behaviors was shown to be due to the internal electric fields induced by the spontaneous polarizations in α-GaN and α-AlN. In addition, the valence-band offsets at the interfaces of these superlattices are also determined. The results are in good agreement with those available from experimental data.

The performances such as the operating-voltage and the brightness of three types of devices: single-layer device, double-layer device and three-layer device, were examined. It is demonstrated that the I-V characteristics of single-layer device depends not on the applied voltage but instead on the electric-field strength, and the brightness increased by a factor of 50 and the operating-voltage decreased when introducing one electron transporting layer or an electron transporting layer and one hole blocking layer between the light emitting layer and the negative electrode. In fact, it is imperative to match the energy level of each layer in the electroluminescent device in order to improve its comprehensive performances.

A polymer thin film electroluminescence (EL) device has been prepared by using plasma polymerization technique. Its basic structure consists of an emitting layer of plasma polymerized naphthalene (PPN) which is sandwiched between two metal electrodes. A uniform blue emission is observed under 8-20 V. Some electrical and optical properties of the device are described. The possible explanations for the blue EL from PPN are discussed.

Semiconductor GaAs microcrystallites were embedded in SiO₂ thin films by magnetron rf cosputtering technique. Structures of the thin films were characterized by transmission electron microscopy, x-ray diffraction and x-ray photoelectron microscopy. Average size of microcrystallites, depending on the substrate temperature during deposition, is 3-10nm. Absorption spectra of the films were measured. Blue shift of absorption edge was observed and discussed according to quantum confinement effect.