We study the Raman scattering of the stretching band from liquid water under pressure up to 6 kbar at 290 K. The result shows that the (v₁)_max intensity decreases with increasing pressure initially and reaches the minimum at about 2 kbar, and increases with the further increase of pressure up to about 4 kbar, then decreases again with the increasing pressure up to 6 kbar. This is in agreement with the behaviour of the average separation r_OO between the nearest molecules under pressure. Additionally, the influence of pressure on water structure is also discussed.

With the help of variable separation approach, a quite general excitation of a new (2+1)-dimensional long dispersive wave system is derived. The chaotic behaviour, such as chaotic line soliton patterns, chaotic dromion patterns, chaotic-period patterns, and chaotic-chaotic patterns, in some new localized excitations are found by selecting appropriate functions.

We study the entanglement in Heisenberg dimer single molecular magnets V⁴⁺ with a strong magnetic field by means of the measure of entanglement called “concurrence”and find that thermal entanglement exists for both the ferromagnetic (FM) and antiferromagnetic (AFM) cases. In the FM case, entanglement vanishes for anisotropic parameter λ = 0 while in the AFM case, entanglement exits in the whole region of anisotropic parameter 0 ≤ λ ≤ 1. Entanglement variations with anisotropic parameter λ, magnetic field B and temperature T are evaluated. We find a critical magnetic field at which the concurrence changes sharply from zero to maximum entanglement.

We investigate the transmission probability of a two-level cold atom through a quantum microcavity when the atom is initially prepared in a coherent superposition of its excited state and ground state. We can control the transmissibility of the atom by this initial coherence. Remarkable step and switch effect are discovered in the atomic transmission for the case of weak and intense quantized fields, respectively.

Quantum correction to entropy of the Kerr black hole arising from Rarita-Schwinger fields is studied by using the Newman-Penrose formalism and brick-wall model. It is shown that contribution of spin to the logarithmic term of the quantum correction is dependent on both the square of spin of the particle and the rotation of the black hole. For different values of a/r₊, the subleading term can increase or decrease, or cannot affect the entropy.

We prepared amorphous carbon films on Si (100) substrates by using a magnetic-field-filtered plasma stream deposition system. Various samples with different sp³-bonded carbon fraction were obtained by changing the bias voltage applied to the substrates. We measured the ellipsometric spectra of various carbon film samples in the photon energy range of 2.0-5.0 eV. We also measured the Raman spectra for comparison. Our results show that the ellipsometric spectra are dependent on the sp³ carbon fraction. We analysed the measured ellipsometric spectra by a simple method, and determined the sp³ carbon fraction semi-quantitatively. The results from the ellipsometry and the Raman spectroscopy show the same tendency of the sp³ carbon fraction as a function of bias voltage. We found that the spectroscopic ellipsometry is a relatively simple, non-destructive method to evaluate the sp³ carbon fraction of the amorphous carbon films.

Local polarization of a sol-gel-derived (Pb,La)(Zr,Ti)O₃ thin film is studied from its piezoelectric response measured by using atomic force microscopy. Topographic and piezoelectric images show that the domain sizes of spontaneous polarization and grain sizes are both within the range of tens to hundreds of nanometers. Nanosized domain arrays have been written in an unpoled region to realize data storage by applying pulse voltage. The results show that the domain sizes grow exponentially when the pulse duration increases.

The x-derivatives of squared Jost solution are the eigenfunctions with the zero eigenvalue of the linearized equation derived from the perturbed Korteweg-de Vries equation. A method similar to Green’s function formalism is introduced to show the completeness of the squared Jost solutions in multi-soliton cases. It is not related to Lax equations directly, and thus it is beneficial to deal with the nonlinear equations with complicated Lax pair.

With an exact chiral symmetry, overlap fermions allow us to reach very light quark region. In the minimum m_ps = 179 MeV, the quenched chiral logarithm diverge is examined. The chiral logarithm parameter δ is calculated from both the pseudo-scalar meson mass m²_ps diverge channel and the pseudo-scalar decay constant f_P channel. In both the cases, we obtain δ = 0.25±0.03. We also observe that the quenched chiral logarithm diverge occurs only in the m_ps ≤ 400 MeV region.

Lifetimes of the high spin yrast states in the odd-proton nucleus ¹³¹Pr have been determined by analysing the Doppler broadened line shapes for the de-exciting γ-rays following the ¹¹⁶Sn(¹⁹F, 4n)¹³¹Pr reaction at a bombarding energy of 95 MeV. The transition quadrupole moments extracted from the measured lifetimes exhibit a considerable reduction near the rotational frequency of 0.42 MeV, at which the J⁽¹⁾ and J⁽²⁾ moments of inertia indicate a band crossing. The experimental result demonstrates occurrence of the nuclear shape change induced by band crossing associated with the alignment of a pair of h_11/2 protons.

The differential cross sections of 22 MeV proton inelastic scattering for the first 1/2⁺ excitation state (E_x = 3.09 MeV) of ¹³C have been measured between 9°and 130°. The broad peak located at ～ 120°, which has been systematically observed in the 0⁺ → 0^-, 1/2^- → 1/2⁺, and 1⁺ → 1^- transitions for the ¹⁶O, ¹³C, and ^14,15N (p,n) charge exchange reactions at E_p = 35 MeV, has been observed for the first time in the present proton inelastic scattering. The present experimental data are analysed by using microscopic distorted-wave Born approximation. From the comparison of present experimental data and theoretical results at forward angles, our analysis indicates the existence of neutron halo in the first 1/2⁺ excitation state of the ¹³C nucleus. In addition, by reasonable modification of shell model wavefunction of the first 1/2⁺ excitation state, we can well describe the experimental form factors of (e,e') and the experimental differential cross sections of (p,p') at incident energy of 547 MeV.

The effect of neutron shell closure N_c = 126 on the prescission particle emission of ¹²⁶Th and ²²⁴Th nuclei is investigated within the framework of an extensive Smoluchowski equation. It is found that there is a large difference in the prescission neutron multiplicity for the two Th nuclei, indicating a strong shell effect in neutron emission. Moreover, shell effects on particle emission are also investigated as functions of excitation energy, angular momentum and nuclear viscosity. The results show that with increasing excitation energy shell effects in prefission neutron evolve from continual strongness to gradual weakness. Both high angular momenta and low viscosity weaken the shell effects on the particle emission.

Considering that the one-turn map can provid a useful and powerful tool to understand the nonlinear dynamics in a designing storage ring dedicated to synchrotron radiation and in a damping ring used as the pre-injector of linear collider, we first expand the Hamiltonian of a charged particle moving along the insertion device (ID) axis to the fourth-order Taylor series, and then construct a second-order symplectic integrator using the Lie map product for the particle passing through one period of the ID. The one-turn map can be obtained by concatenating the Lie map of the whole ID and the rest part of ring.

Temporal distribution of the H atom and H₂ densities in a pulsed microwave hydrogen plasmas has been measured simultaneously by two-photon absorption laser-induced fluorescence (TALIF). The measurement of the H-atom absolute density obtained by NO₂ titration in a flow tube reactor shows that the density of H₂ could be determined by the measured effective lifetime of the TALIF signal via the quenching equation. The H-atom density of about 1.5 x 10¹⁵cm^-3 in both pulsed and stationary phases does not obviously change. It is found that the gas temperature volume effect plays an important role in governing the distributions of the H-atom density and it is mole fraction. The calculated gas temperature is in good consistent with the rotational temperature of H₂ measured by optical emission spectroscopy in pulsed phase.

We present a new method for the numerical calculation of exact complex eigenvalues of Schrödinger equations for a hydrogen atom in a uniform electric field. This method allows a direct calculation for complex eigenvalues without using any auxiliary treatment, such as the Breit-Wigner parameterization and the complex scale transformation, etc. The characteristics of high excited atoms in electric field have attracted extensive interest in experimental aspect, however, the existing theoretical calculation is only up to n = 40. Here we present the computation results ranging from n = 1 to 100. The data for n ≤ 40 are in agreement with the results of other researchers.

The broadening effect in photoelectron angular distributions (PADs) observed by Freeman et al. is studied theoretically. Using a nonperturbative scattering theory developed for multiphoton ionization with the inclusion of spontaneous emission, we calculate the PADs for above-threshold ionization (ATI) peaks. The numerical calculations from our theory reproduce the kinetic-energy dependence and the laser-intensity dependence of PADs of ATI peaks observed by Freeman et al., [Phys. Rev. Lett. 57 (1986) 3156] and provide an evidence for the existance of the ponderomotive momentum of intense laser fields.

Using a formal scattering theoretical approach, we develop a nonperturbative quantum electrodynamics theory to describe laser assisted recombination (LAR), in which an electron initially in the quantized Volkov state recombines with an ion and emits a high energy photon with frequency defined by energy conservation laws. The transition probability is expressed as an analytic closed form and the spectrum of LAR reflects mainly the properties of general Bessel functions. For the case of a fast electron the LAR spectrum is confined in a well-defined range, while for a slow electron, the LAR spectrum exhibits a double-plateau structure.

The Monte Carlo method is applied to study the low-grazing scattering from a vegetation medium. Based on the two-layer model, phase of different fields and volume-surface scattering interaction are taken into account. The scattering coefficient is obtained. The numerical results are in agreement well with the measured data and the vector radiative transfer theory. The results are aslo used to explain the backscattering enhancement and the grazing incidence characteristic.

A novel Yb³⁺-doped four-wavelength double clad fibre laser based on a Fabry-Parot filter, and pumped by a 976 nm laser diode is presented. Its output laser wavelengths are 1085, 1090, 1095, and 1010 nm, respectively. The laser exhibits 0.32 nm line-width, 1.5 W laser output power, 40 dB signal-to-noise ratio and 66% slope efficiency.

A simple division of close-aperture Z-scan curve by open-aperture Z-scan is conveniently used to obtain the nonlinear refractive index. It usually causes an error, which even reaches up to over 50% for Z-scan measurements with a pinhole or a medium with a high nonlinear absorption. Here the influence of nonlinear absorption on the determination of nonlinear refraction by Z-scan is analysed. We suggest that the error can be reduced greatly by a simple analysis of the symmetric features (symmetric method) of Z-scan curves from the
closed-aperture Z-scan curve. As an example, experiments were carried out on CS₂ solution of C₆₀ derivative, symmetric method agrees well with exact simulation.

We study the absorption and transmission spectra, the thermal stability and the green-light (514.5 nm) static optical recording properties of nickel phthalocyanine (NiPc) thin film. It is found that this film occupies suitable absorption and transmission properties, excellent thermal stability (decomposition point > 600°C) and outstanding thermal decomposition characteristics (weight loss in one step decomposition > 60%) for green-light (514.5 nm) optical recording. High reflectivity contrast (> 50%) was obtained at low writing power (5 mW) and short writing pulsewidth (100 ns) using an Ar⁺ laser (514.5 nm) irradiation. Compared with azo in polymer films, the subphthalocyanine film and Sb-Te-Based phase change films, the NiPc film has better green-light static recording properties. These results indicate that metal phthalocyanine is not only a qualified material for near infrared optical recording but also a promising recording medium candidate for green-light DVD-R.

We simulate the changes of the photonics band structure of the crystal in two dimensions with a quasi-fractal structure when it is fined to a fractal. The result shows that when the dielectric distribution is fined, the photonic band structure will be compressd on the whole and the ground photonics band gap (PBG) closed while the next PBGs shrinked, in conjunction with their position declining in the frequency spectrum. Furthermore, the PBGs in the high zone are much more sensitive than those in low zones.

A novel model of two-dimensional periodically poled lithium niobate designed for second harmonic generation of 1064 nm is proposed, in which a rectangular light route is used. The effective length of the sample is longer than the sample real length by 5/3 2^1/2 times. The conversion efficiency enhances greatly without prolonging the periodically poled crystal length.

The coupled nonlinear Schrödinger equations for dispersion-managed soliton (DMS) with the impact of the polarization mode dispersion (PMD) are constructed, and a PMD-suppression approach of DMS is proposed for the first time. Then, based on variational method, the analytical equations of the DMS transmission system with in-line optical filter control are obtained. Finally, in order to investigate the validity of the equations, we present an application sample for practical systems with in-line filter control. The results verify that the control is quite effective and valid.

The onset of oscillatory thermocapillary convection in a floating half zone of 10 cst silicon oil (Prandtl number 105.6) is studied by the three-dimensional and unsteady numerical simulation in microgravity environment (g = 10^-4 g_earth). The results show that the steady and axi symmetric convection, for a fixed liquid bridge volume ratio V_l/V₀ = 1, transits directly to the oscillatory convection if geometrical aspect ratio A is larger than the critical value A_c = 1.25, but transits to the oscillatory convection via the steady and non-axisymmetric flow if A is smaller than the critical value A_c. The result means that there are two bifurcation transitions in a liquid bridge of the large Prandtl number fluid with a smaller aspect ratio A.

A model is developed to calculate the emission spectrum of non-local thermodynamic equilibrium (LTE) plasmas. The Collisional-Radiative model is adopted for non-LTE population calculations. Configuration-averaged rate coefficients that are needed in the rate equations are obtained based on the first-order perturbation theory. The Hatree-FockSlater self-consistent-field method is used to calculate electron wave functions. The present model is applied to the calculation of isoelectronic line-ratio of Cr and Ti, which is usful for plasma electron temperature diagnosis.

Electron-acoustic solitary waves have been studied in an electron-beam plasma system. It is found that the solution of compressive soliton only exists within a limited range of soliton velocity around the electron beam velocity. A compressive electron-acoustic soliton always accompanies with a cold electron density hole. This theoretical model is used to explain the‘fast solitary wave’event observed by the FAST satellite in the mid-altitude auroral zone.

Start-time of magnetic reconnection under typical interplanetary parameters has been numerically simulated by using the two-dimensional compressible magnetohydrodynamic equations with a third-order compact upwind scheme. Magnetic reconnection would occur near the interplanetary current sheet impacted by a plasmoid. Its initiation is associated with the interplanetary plasma parameter β and the momentum of the plasmoid. The higher the β value is, the faster the reconnection takes place. Meanwhile the reconnection occurs earlier with the increase of the plasmoid momentum, and the increase of driving velocity is more effective in initializing the reconnection than that of the plasma density when the other factors are kept to be the same. The evolution of the reconnection with the heliocentric distance is also investigated.

A shock-accelerated flying foil is diagnosed with a chirped pulse spectral interferometry. The shock is pumped by a 1.2 ps chirped laser pulse with a power of ～ 10¹⁴W/cm² at 785 nm irradiating on a 500 nm aluminum film and detected by a probe pulse split from the pump based on a Michelson spectral interferometry. A flying foil of ～ 5.595 x 10^-6g in ～ 400μm diameter was accelerated to ～ 165 nm away from the initial target rear surface at ～ 1.83km/s before ablation.

An analytical formula for the additional beta due to fast fusion-born ions is derived by using the slowing-down approximation from the Fokker-Planck equation under the assumption of negligible loss term. It is found that the fast ion beta in a D-³He fusion plasma at a typical temperature of 55 keV is about 20% of the thermal beta, which is the same ratio as that obtained in a D-T plasma at 20 keV.

The H_α(D_α) line shape in front of the limiter and the wall is measured by two sets of optical spectroscopy multi-channel analysers. The energy distribution is derived directly from the H_α(D_α) line shape, especially showing several molecular processes. The dissociative excitation of molecules is dominating when the local electron temperature is above 10 eV. The D_α line shape is also simulated by the Monte Carlo method, the result shows that the molecular dissociation contributes 57% neutral atoms, 53% emission intensity in front of the limiter, and 85\% neutral atoms, 82% emission intensity in front of the wall. The power loss from molecular dissociation is about 5.6 x 10⁴kW/m^-3 and the molecular dissociation is an important cooling mechanism at the plasma edge.

We study the H₂ molecules confined in single-walled carbon nanotubes by using molecular dynamics simulations and ab initio calculations. It is found that the H₂ molecules at zero-temperature with low density tend to condense. When the linear density of the H₂ molecules in the tube increases, various quasi-one-dimensional solid lattices can be observed at low temperature. When the lattices are heated above room temperature, molecular H₂ liquids with different density can be observed. The quenching behaviour of the H₂ fluids is also examined.

We study the Fermi-Pasta-Ulam lattice model in the presence of a power-law dependence of long-range interaction by virtue of the method of multiple scales. Our results show that an envelope soliton still appears, but it is of different property for the group velocity compared with that of the soliton in the model when long-range interaction is absent.

We study the physics of the formation of vortex states. It is found that the formation of vortex states is affected by two factors, one is the center-of-mass (c.m.) motion, the other is the constraints imposed by symmetry. Only if the vortex structure does not violate the symmetry constraints and is relatively lower in potential energy, it would appear in the first-states.

Starting from classical equations of motion of the charges, we obtain the quantum fluctuations of the charges, and the currents of a mesoscopic capacitance coupled circuit with power source by using a canonical transformation and a unitary transformation. The uncertainty relations between charges and conjugate currents do not satisfy the minimum uncertainty relation, and is independent of the power source.

We investigated the magnetism of systems La_0.7-xGd_xSr_0.3MnO₃ (x = 0.00, 0.10, 0.15, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70) by M-T curves, M-H curves, and electron-spin-resonance (ESR) spectra. The experimental results indicate that the system is in a ferromagnetic long-range order at low-doping level; the samples of x = 0.30 and 0.40 show cluster-spin glass behaviour; and the antiferromagnetic characters are observed at ≥ 0.50. For the samples of x = 0.30 and 0.40, the ESR spectra demonstrate that the phase separation occurs above the Curie temperature.

GaN Nanowires were prepared by the post-nitridation technique. The morphology and structure of GaN nanowires are investigated by transmission electron microscopy and scanning electron microscopy. A strong blue photoluminescence is observed for room-temperature measurement, which attributes to electron transition from DX center to valence band.

The niobate phosphate glasses containing Eu³⁺ ions were fabricated by the melting method. The fluorescence characteristics of the glass at temperatures from 77 K to 700 K were investigated under the excitation of 488 nm light. The results show that the fluorescence intensity of Eu³⁺ ions first increases and then decreases as temperature increases. The temperature-dependent parameters of the crystal fields and the local structure surrounding Eu³⁺ ions were investigated and discussed from the situation of splitting energy level of ⁵D₀-⁷F₁. The results indicate that the distance of europium and oxygen become shorter with the increase of temperature and the coordination number of Eu³⁺ ion is near 8, which does not change with temperature.

Using the model based on the homo-pressure approximation, we explain why the maximum temperature is sensitive to the ambient temperature in the single bubble sonoluminescence. The numerical simulation shows that the maximum temperature inside a sonoluminescing bubble depends on how much water vapor evaporates or coagulates at the bubble wall during the bubble shrinking to its minimum size. While the amount of water vapor inside the bubble at the initial and the final state of the compression depends on the saturated water vapor pressure which is sensitive to the ambient temperature. The lower the saturated vapor pressure is, the higher the maximum temperature is. This may lead to more general conclusion that those liquids with lower saturated vapor pressure are more favorable for the single bubble sonoluminescence. We also compare those bubbles with different noble gases, the result shows that the maximum temperatures in the different gas bubbles are almost the same for those with the same ambient temperature.

CN_x films with x ≈ 0.5 were prepared onto a titanium coated ceramic substrate by using microwave plasma enhanced chemical vapor deposition. As-deposited films were studied by x-ray photoelectron spectroscopy (XPS), x-ray diffraction, and scanning electron microscopy. The films consist of nano-crystalline grains with sites in a range of 20-40nm approximately. The interplanar distance (d-value) of the nano-crystalline structure determined from the peak position of x-ray diffraction was found to be 0.336 nm. This value is consistent with the d-value of graphite. XPS measurements of the N 1 s and C 1 s core levels for the same sample demonstrate two types of bonding structures between carbon and nitrogen atoms, corresponding to sp² C-N and sp³ C-N. It is suggested that the N atoms mainly exist in aromatic rings of the nano-graphite layers by substituting carbon positions with nitrogen. Field electron emission characteristics of the film were tested. The turn-on field of the emission was as low as 1.1V/μm.

Cubic ZnMgO thin films in the (100) orientation were grown on Si (111) substrates by reactive electron beam evaporation at low substrate temperature. X-ray photoelectron spectroscopy (XPS) analyses show that Mg content as high as 75 at.% in the cubic ZnMgO film can be obtained. Secondary ion mass spectroscopy (SIMS) measurement indicates the evidence of Mg richness in the interface between the ZnMgO film and the Si substrate, and it is probably the primary reason to form the MgO-like cubic ZnMgO structures rather than the wurtzite one. The optical band gap of cubic ZnMgO is estimated to be 5.76 eV, which was measured by the transmission spectrum of the cubic ZnMgO film grown on the sapphire substrate under the same growth condition with that on Si (111). The band gap is of 2.39 eV blue shifted compared with that of ZnO (3.37 eV), which should render applications in the fabrication of ZnMgO-related heterostructures.

Based on the model describing the regulation of the P_RM operator region of λ phage proposed by Hasty et al. [Proc. Nat. Acad. Sci. 97 (2000) 2075], we study the steady state probability distribution properties of the model in the presence of correlated Gaussian white noise. We find that the degree of correlation of the noises can affect the form of the steady state probability distribution. When the degree of correlation of the noises increases, the form of the steady state probability distribution changes from a bimodal into a unimodal structure. The steady state probability distribution extrema have also been investigated. We find that noise correlation can change the positions of the extreme value of the steady state probability distribution of the model greatly.

Excitation energy transfer in the isolated light-harvesting chlorophyll (Chl)-a/b protein complex of photosystem II (LHC II) was studied by the one-colour pump-probe technique with femtosecond time resolution. After exciting Chl b by 638 nm beam, the dynamic behaviour shows that the ultrafast energy transfer from Chl-b at positions of B2, B3, and B5 to the corresponding Chl-a molecules in monomeric subunit of LHC II is in the time scale of 230 fs. While with the excitation of Chl a at 678 nm, the energy transfer between excitons of Chl-a molecules has the lifetime of about 370 fs, and two other slow decay components are due to the energy transfer between different Chl-a molecules in a monomeric subunit of LHC II or in different subunits, or due to change of molecular conformation.

New exact solution to the Einstein equations that describe the evolution of cosmological chaotic inflation model is derived. The inflation is driven by the evolution of scalar field with negative potential V() = -V₀ + 1/2m^{2 2}. This includes the solution which is exponential inflation for ₀ > > _f, and then develops smoothly towards the radiation-like evolution for < _f. The spectral indices of the scalar density n_s and the gravitational wave fluctuations n_g are computed. The value of n_s lies well inside the limits set by the cosmic background explorer satellite.