The far infrared reflection spectra of n GaAs_(1-x)_P_x_ with x=0.328 and x=0.40 are investigated in the frequency range of 40-700 1/cm and the temperature range of 4.2-300K. The important physical parameters describing the optical phonons, Plasmon and LO phononplasmon coupling mode of the material and infrared optical constants are obtained by the multioscillator fitting and K-K relation calculat...
For poly-crystalline semiconduetor film deposited on an insulator and then recrystallized by a laser beam, the influence of the substrate upon recrystallization of the film was analyzed theoretically. We found the critical laser power necessary for solid-liquid phase transition to take place, will change to a lower value as the poor thermal conduction of insulating substrate being reasonably consi...
The electronic energy band structures of CeSn_3 and CeIn_3 are studied with LMTO-ASA method. The behavior of the f-electrons of Ce and the hybridization between f-orbitals and the s, p, d orbitals of non-f-atoms are discussed. The density of states and energy bands are investigated, especially in the vicinity of Ef,
The oxide precipitates (1000-6000A) were separated from as-grown CZ silicon crystal containing the swirl defects by means of chemical etching method. The selected-area electron diffraction analysis of the precipitates, which had been prepareted into the extraction replica specimens, was carried out in TEM. Simultaneously, the morphology of the swirl defects in silicon thin foil specimens was obser...
The phenomenological atomic potential model with analytical solutions is employed to obtain the wave functions of the Rydberg states (10≤n≤40) and the oscillator strengths of the ns--n'p ,np--n'd, and nd--n'f transitions between them. The results are very close to those obtained by the CA method. These results show that there exists a kind of sealing law for the above oscillator strengths.
Montmorillonite samples treated at different temperatures had been studied by XRD. The (00l) reflections of some samples disappeared, and reappeared under some conditions. The crystallographic significance and the possible phase transformation had been discussed.
Taking account of two-and three-body interaction of the nearestneighbours, the acoustic modes of NXN square lattice is solved in harmonic approximation. The boundary coupling effect leads to physical pictures of phonons different from those in infinite lattice. The standing wave phonons can only be classified according to space species, and the wave vector losses it’s sense. Numerical computation ...
In this paper, the critical exponents of the Potts model are calculated by using the exact decimation with mean-field approximation method. The results obtained are in good agreement with that of the exact calculation. The accurary of this method is better than other renormalization group methods.
The effects of cold plasma and conducting end plates on interchange instability of finite-length hot electron plasma are studied. A dispersion relation including line-tying is deriver, and new stability criteria are found. Strong line-tying effect can greatly reduce the threshold of density ratio needed for stabilizing interchange mode of hot electrons. The modes with low in and long wavelength m...
The X-ray K absorption spectra of iron in metglas Fe_80_B_20_ and Fe_80_Si_6_B_14_ are measured, using the rotating anode X-ray generator and the EXAFS spectrometer with bend crystal. The structural parameters of near neighbor of these metglases are determined by EXAFS. Besides, their XANES are also measured. While comparing the XANES of iron inmetglases with that in a-Fe, FeB andFe_2_B, we discov...
Hall effects of amorphous InSb and its metastable intermediate phases which appear in the process of thee crystallization phase transition have been studied. Experimental results show that the conduction of the electron is dominative in the metal-type amorphous InSb and the conduction of the hole is dominative in the semiconductor-type amorphous InSb. The first jump of the conductance is a process...
By use of the spinor-spinor Bethe-Salpeter equation of field theory, we assumed a phenomenolgical “flatl bottom” hadronic potential which is relativistically covariant. And the meson wave function was obtained in the momentum space.
It is shown that for general compact simple Lie groups and arbitrary value of coupling constant __ _, the equal time current algebra of the two dimensional non-linear __ model with Wess-Zumiuo term is a Kac-Moody algebra with center charge.
In the amorphous alloys Nb_(1-x)Ni_x_(x= 0 .564 , 0 .595 , 0.65 ), we observed the double Curie temperature phenomenon of itinerant electron magnetism and also the typical susceptibility cusp for spin glass freezing. In this alloy system, both itinerant electron magnetism and localized magnetic appear very clearly.
The hydrogen adsorption on GaAs and InP surfaces was studied by high resolution electron energy loss spectroscopy (HREELS). The stretching vibration modes of Ga-H,As-H, In- H and P-H bonds corresponding to different energy loss peaks in the spectra were all observed. However, the As-H vibration mode was usually confused with Ga-H“Phonon echo”peak which is the Ga-H vibration mode plus an optical su...
The presence of surface state originated from T-3+ ion on reductive SrTio3 been observed. The action of Ti-3+ on photodecomposition of water and the action of light irradiation on regeneration of activity are analysed.
The expression for intensity distribution and computer simulated images of screw dislocations with Burgers vector l/2 (111) viewed end-on in gernet crystals subjected to a long-range strain have been obtained by considering only the anisotropy of the photo-elastic property of the material. The computer-simulated images of end-on screw dislocations show two fold symmetry with a pair of dark and bri...
Based on the characteristics of superionic glasses and a physical picture of unified theory of the low-frequency fluctuation, dissipation and relaxation phenomenon, the transport features of a non-Markovian process of conduct ions are explored. The theory predict that the frequency independent conductance follows a simple Arrhenius type dependence on temperature at high temperatures, The theory ca...
In this paper, the influence of crystal field on the shift of center of gravity of rare earth ion are discussed theoretically. The shifts of the center of gravity of‘I , state due to the J-mixing effect occur in 15 crystals doped Nd3+ are calculated. The results show that the splitting width of spectral term,
The volume compression of a-LiIO_3_ has been studied by X-ray diffraction in a diamond anvil cell up to 23.0GPa at room temperature. The anisotropic compression of lattice was observed. The ratio of c/a of parameters decreased with a rate of -6.187x 10**(-3)/GPa with pressure. The bulk modulus of normal pressure and its first pressure deviative have been determined to be equal to 39.2 and 3.787GPa...