Homogeneous ensembles are introduced and their distribution functions in phase space are given. A comparison between these distribution functions and those obtained from quantum stationary systems is made. It is shown that the quantum stationary systems are completely equivalent to homogeneous ensembles in the classical limit.

After introducing an unitary transformation to decouple the correlations of the different components of the Dirace equation, we found the exact solutions of the Dirace equation with a finite size linear scalarlike potential analytically. The transmission amplitude and the reflection amplitude are given.

It is shown in this paper that there is a difficulty in conventional black hole thermodynamics. To overcome the difficulty we introduce a “surface” near the event horizon as an additional thermodynamical object. The mass and entropy of the additional “surface” are the same as the correction of mass of Schwarzschild black hole obtained in the back-reaction program up to a constant factor. This implies that some effects of back reaction an automatically considered in our thermodynamic phenomenological treatment.

The decay Z→π⁰γ, for which a recent study found a sizable rate, is examined. It is shown that the rate for Z→π⁰γ is calculatable in the standard model and the result of a calculation shows that the rate is much suppressed.

Instead of two-kink system, two-breather system under sum ansatz is quantized. A covariant meson-breather interaction to the one-meson range and to the leading nonstatic order is obtained. All of the results depend on breather internal variable θ .

We present our theoretical study in electronic structures of molecular Rydberg states for some diatomic molecules along the second row in the periodic table which involve binding between atomic 2s and 2p valence orbitals.

Under laser excitation of vaporized zinc to 4s4p ³P⁰₁ metastable level, the emission bands at violet and ultraviolet ranges were observed. The radiative decay time of 20 ns has been measured for both bands. The temporal behavior and excitation condition indicate that they are possibly from the same state ³Σ⁺_u of Zn₂ molecule. The wavelength range of the two bands coincides with theoretical predication.

The scaled potentials were used to discuss the vibrational quantum defects of alkali-halide molecules by using the fully quantal Milne equation method and the quasiclassical Wentzell-Kramers-Briilouin approximation. This allowed us to obtain a universal function and its limit value for the charge-transfer states of different alkali-halide molecules.

The observation of Rabi sideband of Na atom shows the two-level dressed atom model is over simplified. Using a multi-level model and considering the time evolution of the laser pulse the experiment is well explained.

Photoacoustic (PA) effect induced in solids by X-ray absorption was observed, and the experimental signals were obtained on graphite and copper samples as functions of the chopping frequency. Theoretical calculations and detailed discussions were made to interpret the experimental results using Rosencwaig-Gerho (RG) theory.

GaAs films made by molecular beam epitaxy with thicknesses ranging from 0.9 to 1.25μm on Si have been implanted with Si ions at 1.2MeV to dose of 1x10¹⁵/cm². A rapid infrared thermal annealing and white light annealing were then used for recrystallization. Crystalline quality was analysed by using backscattering channeling technique with Li ion beam of 4.2MeV. The experimental result show that energy selection is important for obtaining better and uniform recrystallized GaAs epilayers.

Previous measurements of the single crystal elastic constants of NiO by ultrasonic techniques have been in wide disagreement. This paper gives the results of recent data obtained from several well characterized NiO single crystals. The present results for the antiferromagnetic phase at 298K are different from the previous data and rectify certain questions about the elastic anisotropy ratio C₄₄/C' and bulk modulus K_s.

The Ar ion implantation induced changes of structure and transport properties of YBa₂Cu₃O_7-x thin films were studied as a function of fluence. Both the zero resistance temperature T_c and the critical current density Jc decrease rapidly with fluence, however, the transition temperature onset almost remains constant at low fluences. At dose of 1.2x10¹³Ar/cm², the sample has a metal to semiconductor phase transition. When the fluence further increases, a crystalline to amorphous phase transition occurs, and the sample becomes insulator.

In this work we measured Hall effect and thermoelectric power as well as transmission and reflection spectra in the visible and near-infrared (IR) regions, and calculated the optical gap energy for Sb-doped SnO₂ films grown on 7059 glass substrate by chemical spray technique. Experimental results show that the optical gap energy increases with increasing annealing temperature, and the effective mass m* in relation to the free-electron mass m₀ for a given carrier concentration n and scattering parameter p is also given.