Volume 4 Issue 5

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Original Articles
HOT-CARRIER ENERGY-TRANSFER RATE IN GaAs-AlGaAs HETEROSTRUCTURES
LEI Xiaolin
Chin. Phys. Lett. 1987, 4 (5): 193-196 .  
Abstract   PDF(pc) (45KB) ( 531 )
Hot-carrier energy-transfer rates in GaAs-AlGaAs single and multiple heterostructures are studied based on a balance-equation approach recently developed. The electron temperature is almost a universal function of the energy-transfer rate per carrier, irrespective of the system geometry, electron density and impurity scattering, and that in the case of optic phonon scattering, the dynamic and high-field effects eliminate most of the screening.
PRESSURE LAW OF TURBULENT JET NOISE
MA Dayou(MAA Dah-You )
Chin. Phys. Lett. 1987, 4 (5): 197-200 .  
Abstract   PDF(pc) (46KB) ( 465 )
Lighthill's U8-law is discussed and an equivalent is derived in terms of pressures. This is further developed to include the turbulent noise from choked jets. The results agree well with experiments.
TWO-PHOTON OPTICAL BISTABILITY IN RAMAN PROCESSES
ZHENG Qianbing*, CAO Hongli
Chin. Phys. Lett. 1987, 4 (5): 201-204 .  
Abstract   PDF(pc) (46KB) ( 471 )
The first experimental observation of two-photon optical bistability in Raman case (both in ordinary stimulated Raman scattering and Raman laser) is reported. The active control character in two-photon bistability is verified. It is also shown that the bistability plays an important role in efficient stimulated Raman scattering conversion.
THE SPECTRAL ASYMMETRY AND FRACTIONAL CHARGE IN A BACKGROUND OF 1/n-CONTRACTED SOLITON
KONG Fanmei, YANG Zhenqing
Chin. Phys. Lett. 1987, 4 (5): 205-208 .  
Abstract   PDF(pc) (35KB) ( 398 )
The Dirac equation with a 1/n -contracted Sine-Gordon soliton as background is solved. The results show a spectral transference characterizing the topology of the back-ground field, which leads to a spectral asymmetry and a 1/n fractional charge.
AN EXPERIMENTAL INVESTIGATION ON ADHESION OF IRON IN CONTACT WITH IRON AND COPPER
SUN Jiansan, QI Zhenzhong, LIU Ling, YAO Weiguo
Chin. Phys. Lett. 1987, 4 (5): 209-212 .  
Abstract   PDF(pc) (45KB) ( 449 )
Fe in contact with Fe and Cu was investigated in a vacum of 10-7 pa using a pin sample to contact with a flat sample. The adhesion bond force and adhesive strength have been measured. The adhesive strength of Fe-Cu und Fe-Fe are 130±20kg/mm2 and 70±10kg/mm2 at 298K, respectively. These strong interactions arise from the chemical bonding, instead of Van der Waals interaction.


STUDY ON PERTURBATION LAYER OF SILICON WITH "MIRAGE EFFECT" TECHNIQUE
ZHANG Xiaorong, GAN Changming, LI Youzhi, GUAN Susheng, TAN Ruiling*
Chin. Phys. Lett. 1987, 4 (5): 213-216 .  
Abstract   PDF(pc) (50KB) ( 516 )
The relative changes of thermal diffusivity lengths in ion-implanted and unimplanted silicon wafers were studied with "mirage effect", i. e. OBD techique. The fundamental principle, experimental results and feasible explanation are presented.
GLOBAL ANALYSIS OF RELATIVE SPATIAL DIFFUSION OF CHARGED PARTICLES IN A MAGNETO-TURBULENT PLASMA
WANG Haida*, QIU Xiaoming(S.M.Chiu)
Chin. Phys. Lett. 1987, 4 (5): 217-220 .  
Abstract   PDF(pc) (43KB) ( 425 )
In this paper an analytical theory for stochastic motion of charged particles in magneto-turbulent plasma is founded on the whole time region. A set of nonlinear differential equations has been derived for describing the relative spatial diffusion of charged particles. Some explicit results are obtained for the cases with weak and strong magnetic field. It is found that, for the diffusion in the present system there are some new and interesting properties which do not exist in unmagnetized one.
DISTRIBUTIONS OF VALONS IN NUCLEI AND EUROPEAN MUON COLLABORATION EFFECT
ZHANG Chaoxi (CHANG chaohsi), ZHU Wei*
Chin. Phys. Lett. 1987, 4 (5): 221-224 .  
Abstract   PDF(pc) (39KB) ( 404 )
The new European Muon Collaboration (EM) effect in the low and the main regions of x may be understood by means of the valon picture, i.e., the valon structure functions are universal but valon distribution function of a nucleon is distorted when the nucleon is combined into a nucleus.
THE RETURN CURRENTS IN PULSAR MODELS
TAN Jilin*, LIANG Shaorong
Chin. Phys. Lett. 1987, 4 (5): 225-228 .  
Abstract   PDF(pc) (39KB) ( 500 )
The modified Eulerian equation has been obtained by taking the radiative drag into account. Using this equation, we have found the trajectory equation of charged particles beyond the light-cylinder and solved it numerically without any hypothesis that had to be used in the literature. Especially, it has accounted for the stability of the return currents, which was not mentioned before.
HARMONIC OSCILLATORY POTENTIAL AND FISSION RATE AT LARGE FRICTION CONSTANT
LU Zhongdao, CHEN Bin, ZHUO Yizhong, HAN Huiyi*
Chin. Phys. Lett. 1987, 4 (5): 229-232 .  
Abstract   PDF(pc) (47KB) ( 435 )
The fission potential, fission rate and probability distribution are calculated by solving extensive smoluchowski equation. This potential is compared with the smoothly-connected harmonic oscillatory potential and the fission rate is compared with that given by Kramers.
SUPERCONDUCTIVITY OF Sr-La-Cu-O THIN FILMS
LI Lin, ZHAO Bairu, LU Yong, WANG Huisheng, ZHAO Yuying, SHI Yinhuan
Chin. Phys. Lett. 1987, 4 (5): 233-236 .  
Abstract   PDF(pc) (46KB) ( 446 )
High Tc Sr-La-Cu-O thin films have been successfully prepared by magnetron sputtering method. Their superconducting transition temperatures Tc are determined to be 25-27.3K and the transition widths 7.5-8.5K.
A SPACE-PERIODIC SOLUTION OF THE EQUATION OF A FERROMAGNETIC CHAIN
CHEN Zongyun*, HYANG Nianning**, YAN Jiaren
Chin. Phys. Lett. 1987, 4 (5): 237-239 .  
Abstract   PDF(pc) (28KB) ( 466 )
It is shown that the space-periodic solutions of the equation of a ferromagnetic chain(the socalled Landau-Lifshitz equation) can be obtained by solving the Lax pair equations of the nonlinear Schödinger equation with the space-periodic potential in the case of the zero spectrum parameter. As an example, the one-band solution is found by this method.
12 articles