Vol. 30, No. 8 (1981)
1981-04-20
CONTENT
1981, 30 (8): 1003-1010.
doi: 10.7498/aps.30.1003
Abstract +
According to the general theory of relativity, The force is not an covariant quantity under general coordinate transformations. Different coordinate conditions will lead to different damping forces. It will be convenent to find out the physical coordinate system in which the calculated value of the damping effect is the same as or nearest to that observed on earth. We expect that this physical coordinate system should be free from spurious non-transverse gravitational waves at infinity. In this coordinates the change of orbital period P due to emission of gravitational waves is given by P=-6.5×10-12(m1m2)/M⊙2((m1+m2)/m⊙)-1/3.
1981, 30 (8): 1011-1019.
doi: 10.7498/aps.30.1011
Abstract +
The second order ion trajectories in crossed toroidal electric and inhomogeneous magnetic fields are derived by means of the Fermat's principle and expressed in energy deviation. The ion trajectory formulae may be transferred into velocity or momentum deviation. The transfer formulae between different deviations are given in detail.
1981, 30 (8): 1020-1029.
doi: 10.7498/aps.30.1020
Abstract +
A renormalization procedure for the perturbative manipulation of Vlasov-Poisson equation has been proposed in this paper. By the graphical expansion method the theory is shown to be renormalizable to any order, and the renormalized propagator is given. The physical meaning of the coherent terms and the absolute incoherent terms is analyzed. The correct expression for the renormalized dielectric function is given and its significances are discussed. By comparison with previous renormalization theory, it is pointed out that this procedure is a true complete renormalization.
1981, 30 (8): 1030-1040.
doi: 10.7498/aps.30.1030
Abstract +
The four-dimensional space-time of special relativity is augmented with a fifth dimension to take into account the gauge transformation of the electromagnetic potentials. And in doing this, a new field is introduced purely from dimensional consideration. It will be shown in this paper that this field plays an especially important role inside the electron. It gives rise naturally to the Poincare stress needed for maintaining dynamical equilibrium within an extensive electron, it also reflects the dielectric constant and permeability of the medium within. It thus appears feasible to adopt a fluid structure for the extensive electron, and stable solution for the motion of the fluid particiea has been obtained in general. The electrodynamics within the electron has also been obtained, and no physical solution with spherical symmetry exists. Axially symmetrical solution probably exists, which will be discussed in a subsequent paper.
1981, 30 (8): 1041-1055.
doi: 10.7498/aps.30.1041
Abstract +
This paper is the second part of a theory of the coherent propagation of light wave in semiconductors. After considering the interaction between electrons, the problem of a semiconductor interacting with light is discussed and the equation of exciton polarization wave excited by light wave is obtained. We point out that the equation can be approximated by a set of linear ones and the exciton polarization wave can be regarded as a Bose field only in the limit of low excitation. In this paper, the problem of coherent excitation of discrete exciton level is also discussed specifically. It is shown that the discrete exciton level system excited coherently is approximately equivalent to a two-level atom system excited by light wave in which the difference of energy level is dependent on the degree of excitation and the density of equivalent "two-level atoms" is determined by features of the exciton state wave function.
1981, 30 (8): 1056-1066.
doi: 10.7498/aps.30.1056
Abstract +
This paper is the third part of a theory of the coherent propagation of light in semiconductors. Based on the previous papers (Ⅰ) and (Ⅱ), the Maxwell-Bloch equation describing the coherent propagation of light in semiconductors is derived; the equation is then used to discuss a number of possible effects of coherent propagation in both interband transitions and exciton transitions. In particular, the phenomena of self-induced transparency are analysed, and it is shown that the phenomena may occur in the above two transitions.
1981, 30 (8): 1067-1076.
doi: 10.7498/aps.30.1067
Abstract +
The semiclassical laser theory proposed by Lamb for two-level system is extended to the case of dye lasers. Mode coupling equations are deduced, and a discussion is given.
1981, 30 (8): 1075-1099.
doi: 10.7498/aps.30.1075
Abstract +
The thermal effects arising from the lasing process in orthorhombic YAP crystals have been discussed theoretically in this paper. Mathematical expressions have been given for the thermal distribution, stress-strain distribution, birefringence and thermal lens effect of the YAP crystals as well as the isogyre pattern of a YAP rod placed between crossed polarizers. It is shown that calculated results agree qualitatively with the observed thermal effects.
1981, 30 (8): 1077-1084.
doi: 10.7498/aps.30.1077
Abstract +
We have studied the interaction between the 1010 W Nd glass laser pulses with a leading edge of about 1ns and several planar targets made of deuterium-contained materials. In our experiments, the neutron yields, electron temperature and various characteristics (such as reflectivity, temporal, spatial and spectral structure) of the backward-reflected laser light from the plasmas have been mainly measured.
1981, 30 (8): 1100-1105.
doi: 10.7498/aps.30.1100
Abstract +
The object of this article is to present the experimental facts about the spiral crystals. The spiral crystal is just like a straight crystal bar with definite orientation coiled on a cylindrical surface. It is not formed spontaneously, but is formed under control. Some problems on spiral crystal are discussed.
1981, 30 (8): 1106-1110.
doi: 10.7498/aps.30.1106
Abstract +
The grown-in defects in a synthetic quartz crystal grown from a 2-cut seed plate have been surveyed by X-ray topography and ion probe method. Besides usual dislocations, it has also been found some rare fault surfaces which have not been reported so far. The configuration, fault vector and formation of the fault surfaces are discussed.
1981, 30 (8): 1111-1116.
doi: 10.7498/aps.30.1111
Abstract +
We propose a possible origin of FME linewidth anisotropy shown in mechanically polished YIG and BCVIG single crystals. The stresses left on the surface of the spheres of these crystals couple with the magnetization through the magnetostriction effect, and thus give rise to an additional linewidth, which is anisotropic due to the anisotropic magnetostrictive constant. Supposing that the damaged layer is mainly composed of high density dislocations, a relation between the FME linewidth anisotropy and the magnetostriction constants is deduced based on micromagnetism theory and the two-magnon scattering process. From the measured linewidth anisotropy of YIG, we evaluated the dislocation density of the surface layer to be 5.4×1010/cm2.This relaxation process shows that in order to further reduce the linewidth of an ultra-low linewidth polycrystalline material, suppressing the magnetostriction constant may play an important role.
1981, 30 (8): 1117-1121.
doi: 10.7498/aps.30.1117
Abstract +
There are twe problems involved in the C1 chemisorption on the GaAs (110) surface, one is whether Cl adsorbs on the relaxed surface or on the unrelaxed one, while the other is whether Cl bonded with the surface anion or with the cation. The present work indicates that the Cl atom adsorbs on the relaxed GaAs (110) surface and is bonded with the surface As. The density of states calculated from this configuration seems to agree well with existing experimental results.
BRIEF REPORT
1981, 30 (8): 1122-1126.
doi: 10.7498/aps.30.1122
Abstract +
In this paper, a Scalar Eelativiatic Green's Function method ( SRA-KKR) neglecting spin-orbit coupling effect has been proposed for the energy band calculation. With this method, only a few modifications to the Non-Relativistic Green's Function method would be needed in order to obtain the relativiatic effect on the electronic band structure of solid.
1981, 30 (8): 1127-1131.
doi: 10.7498/aps.30.1127
Abstract +
On the basis of a recent discussion on the analytical properties of the first order equation for Tc, we show, by concrete examples, that the radius of convergence of the series for superconducting critical temperature is so sensitive to the high-frequency behaviors of the phonon spectral function, that it is inadequate for it to serve as a critical quantity in the criterion for dividing superconductors into type A and type B.
1981, 30 (8): 1132-1136.
doi: 10.7498/aps.30.1132
Abstract +
The analysis of the present paper shows that in the case of |zph|c series solution, although does not converge outside the convergence circle determined by the singular point zph, is an asymptotic power series so long as 1/λ is less than [0.63+3μ+(1/Λ1)] 1/Λ1, where 1/Λ1=min(|z|,1);μ+(x)=(1-2μ*x)μ*.
1981, 30 (8): 1137-1140.
doi: 10.7498/aps.30.1137
Abstract +
In the present paper, the theory and the Tc formula which were presented in the previous paper of this series, are extended to the case of μ*≠0. The result obtained by the authors is as follows Tc=(2γ)/πωlog·(ωlog/ωc)(μ*/(λ-μ*))·exp{-(1+λ)/(λ-μ*)}. Inγ =C = 0.5772 is Euler constant.
1981, 30 (8): 1141-1149.
doi: 10.7498/aps.30.1141
Abstract +
Single crystals of picriafeltarragenin epoxy compound, C30H44O6, belong to space group P(212121) with lattice parameters a =28.373 (9)?, b=10.667 (5)?, c = 9.115 (4)? and 4 molecules in the unit cell. The intensities of 2890 independent reflectionsau collected using the PW-1100 fourcircle diffractometer. The structure was solved with MULTAN 78 program and refined to a final R = 0.084 by block diagonal least square method. Positions of all the hydrogen atoms were obtained from the difference Fourier synthesis. The shortest distance between two molecules is 3.5?.
1981, 30 (8): 1150-1154.
doi: 10.7498/aps.30.1150
Abstract +
It is more difficult to find an exact solution of the field equations in the gauge theory of gravitation as compared with finding that in Einstein's theory. As far as some problems in physics are concerned, however, it is sufficient to obtain a Newtonian approximate solution and a post-Newtonian approximate solution. In this note the L?U(1) gauge theory of gravitation is discussed. A special exact solution and the approximation to first order to the spherically symmetric and static field of a charged mass point are obtained.
