Current Issue

Volume 5 Issue 5
Online Date:
Previous Issue    Next Issue
Original Articles
ELECTRONIC STRUCTURE AND EQUATION OF STATE OF COMPRESSED COPPER--AN ASW CALCULATION
JIN Qinghua, DING Datong, WANG Dingsheng*
Chin. Phys. Lett. 1988, 5 (5): 193-196 .  
Abstract   PDF(pc) (46KB) ( 389 )
The band structure and pressure (at T=0) as functions of compression V0/V have been calculated for copper in terms of Augmented Spherical Wave (ASW) method. The calculation covered the V0/V values from 1 up to 10. The results illustrate that ASW method is at least as accurate as other standard methods in this field.
ION ENDUCED ADHESION BETWEEN METALS AND OXIDES
CHENG Guoan*, LI Hengde*, LIU Baixin
Chin. Phys. Lett. 1988, 5 (5): 197-200 .  
Abstract   PDF(pc) (46KB) ( 361 )
The enhancement of adhesion between deposited metal layers ( Ti and Cu) and the oxide substrates at RT and 300°c respectively was studied by argon ion irradiation to various doses. The experimental results showed that the adhesive strength increased after a threshold dose irradiation and reached as aturation value at higher doses in all metal/oxide pairs. RBS spectra showed that chemical reaction had taken place in Ti /oxide case, while in Cu/oxide case, both RBS and XPS analysis showed that no evidence of such reaction had been induced.
MULTISTABILITY PHENOMENA IN DISCHARGE PLASMA
JIANG Yong, WANG Haida, YU Changxuan
Chin. Phys. Lett. 1988, 5 (5): 201-204 .  
Abstract   PDF(pc) (49KB) ( 362 )
Multistability phenomena in V-I characteristic of discharge plasma have been observed in a Double Plasma device. These effects are explained using catastrophe theory together with the consideration of the negative resistance of plasma.
STIMULATED RAMAN OSCILLATION FROM THE DROPLETS BY ULTRASHORT LASER PULSE
QIAN Shixiong, WANG Jun, LI Yufen
Chin. Phys. Lett. 1988, 5 (5): 205-208 .  
Abstract   PDF(pc) (43KB) ( 408 )
We have measured the picosecond Stokes oscillation from CC14, C6H6 and other droplets with about 70 micrometer diameter. The obtained oscillation can reach 8th order. The explanation for the differences between the Stokes oscillations with nanosecond and picosecond pumping is given.
SOME REMARKABLE BEHAVIORS BELOW 125K IN HIGH Tc SUPERCONDUCTORS
ZHAO Guomeng, WANG Ruilan, LI Hongcheng, CHENG Xiangrong, LI Lin
Chin. Phys. Lett. 1988, 5 (5): 209-212 .  
Abstract   PDF(pc) (44KB) ( 389 )
The resistivity, Meissner effect and specific heat measurements were carried out on high Tc superconductor Ba2GdCu3O7-y with zero-resistivity at 95.5K. It was found that the deviation of resistivity from linear behavior below 125K seemed not to originate from precursory signal of superconductivity but from possible lattice softening that may play an important role in 90K superconductivity.
MöSSBAUER STUDY ON Eu-Ba-Cu OXIDE SUPERCONDUCTOR
LIU Rongchuan, HU Zheng, JIN Xin, SHAO Huimin WANG Guiqin, ZHAO Jiwan, HSIA Yuanfu
Chin. Phys. Lett. 1988, 5 (5): 213-216 .  
Abstract   PDF(pc) (40KB) ( 457 )
Onset of superconductivity of the new high Tc superconductor Eu-Sa-Cu-O was found to be 92K. The valence of Eu ion and the Debye temperature of this superconductor were determined using Mössbauer spectroscopy. The experimental results show abnormal changes of isomer shift and lattice-softening nearby the transition temperature Tc. It seems that high Debye temperature is not a necessary condition for this high Tc superconducting system.

APPLICATION OF THE EMBEDDED ATOM METHOD TO PHONON DISPERSIONS IN COPPER
LUO Ningsheng, XU Wenlan, SHEN Shuechu(S .C .Shen), YE Yiying*
Chin. Phys. Lett. 1988, 5 (5): 217-220 .  
Abstract   PDF(pc) (42KB) ( 470 )
The force constants between planes in lattice dynamics have been derived from a new model set by the Embedded Atom Method(EAM), based on tile results from density-functional theory. The semiempirical functions for Cu have been obtained by EAM, and the force constants between planes of Cu are calculated, which produce phonon dispersions in agreement with experiments.
HALL EFFECT IN SUPERCONDUCTING OXIDE Ba-Y-V-Cu-O
ZHAQ Yong, XIA Jiansheng, HE Zhenhui, SUN Shifang, ZHANG Qirui*, QIAN Yitai**, CHEN Zuyao**, PAN Guoqiang**
Chin. Phys. Lett. 1988, 5 (5): 221-224 .  
Abstract   PDF(pc) (50KB) ( 444 )
Results of resistivity, ac magnetic susceptibility, and Halleffect measurements for Ba1.2Y0.9V0.9Cu307-δ are reported. The positive value of Hall constant indicates that the material conducts via holes with a carrier concentration of 1.6x1021cm-3 at room temperature. A large anomaly in RH near Tc is observed.
MATERIAL PROPERTIES ON SURFACES AND INTERFACES
A.Grauel
Chin. Phys. Lett. 1988, 5 (5): 225-228 .  
Abstract   PDF(pc) (42KB) ( 524 )
We present a multi-constituent thermodynamical field theory for media in curved interfaces and surfaces. Moreover we derive a generalized transport equation and specific field equations.
SUPERCONDUCTIVITY CAUSED BY STRONG CORRELATION
FENG Shiping, MA Benkun*
Chin. Phys. Lett. 1988, 5 (5): 229-232 .  
Abstract   PDF(pc) (32KB) ( 373 )
We used the Anderson lattice Hamiltonian to discuss the superconductivity of two-band strong correlation systems and found that superconductivity of these systems is caused by strong correlations.
STUDIES ON UNIVERSALITY IN TWO DIMENSIONAL FRACTAL MEDIA
ZHANG Min*, TAO Ruibao
Chin. Phys. Lett. 1988, 5 (5): 233-236 .  
Abstract   PDF(pc) (30KB) ( 371 )
Elasticity and electricity ( dielectricity and conductivity) equations in two-dimensional inhomogeneous media are compared. In the case of perpendicular vibration, the elasticity equation can be transformed in to the exact formulation of the dielectricity one: therefore, electricity and elasticity belong to the same universal class and have the same size scaling exponent in the fractal system.
SEARCH FOR FOSSIL TRACKS FORMED BY COSMIC NUCLEARITES IN METEORITES
CUI Huanhua*, O.Eugster**, KE Wei*, P.LE Coultre***, TANG Xiaowei*
Chin. Phys. Lett. 1988, 5 (5): 237-240 .  
Abstract   PDF(pc) (28KB) ( 519 )
Based on the proposal by Witten, De Rujula and Glashow, we carried out the experimental search on two meteorites for the fossil tracks formed by cosmic nuclearites with masses ranging from M~6xl0-4g up to very large mass. An upper limit 2km-2y-1(2πsr)-1 was obtained for the cosmic nuclearites with masses larger than 6xl0-4g which passed through these meteorites.
12 articles