Current Issue

Volume 8 Issue 11
Online Date:
Previous Issue    Next Issue
Original Articles
Quark Mass Corrections to the QCD Finite Energy Sum Rules for the O++ scalar Glueball
LIU JuePing, LIU DunHuan
Chin. Phys. Lett. 1991, 8 (11): 551-554 .  
Abstract   PDF(pc) (84KB) ( 411 )
The properties of the O++ scalar glueball is investigated in the fremework of the quantum chromodynamics finite energy sum rules. The mass and width of such glueball are predicted to be 0.62GeV and 62Mev respectively. The effect of non-vanishing quark masses turns out to be not negligible.
Electric Dipole Moment of W-boson Through Neutral Higga-Boson Exchange
LI Chongsheng, FANG Zhenyun, HU Bingquan
Chin. Phys. Lett. 1991, 8 (11): 555-558 .  
Abstract   PDF(pc) (84KB) ( 462 )
We compute the electric dipole moment generated at two-loop for the W-boson in the Weinberg-Higgs model in which the CP violation is mediated by neutral Higgs-boson exchange. We also compare our results with the others relative to the problem in the literature
Chaos in an Ar+ Composite Resonator Laser Using KNSBN;Cu Crystal Self-Pumped Phase-Conjugator
CAO Yongxing, BA Enxu
Chin. Phys. Lett. 1991, 8 (11): 559-561 .  
Abstract   PDF(pc) (99KB) ( 538 )
Observation of the dynamics in a single-mode Ar+ composite resonator laser using KNSBN;Cu crystal self-pumped phase-conjugator is reported. The sequence of instabilities occurring on gain change corresponds to the transition the chaos of the logistic equation. Period-doubling route to chaos, and period-5, -3,-3×2, and -2 together with -3 windows in the chaotic range were observed. The strange attractor which is similar to that of the forced Duffing equation is obtained by reconstructing phase-space pictures of the system.
measurement of Third Order Hyperpolarizability of Some Dyes
GONG Qihuang, CAO Aimin, XIA Zongju, ZOU Yinghua
Chin. Phys. Lett. 1991, 8 (11): 562-565 .  
Abstract   PDF(pc) (85KB) ( 455 )
A degenerate four-wave mixing experiment with the solutions of some dyes has been performed using 10ns pulses at 530nm. Large resonant and off-resonant third order hyperpolarizabilities were obtained.
Frequency Characteristics of the Satureted Gain in Nonequilibrium Gas Flow and Doppler-Broadened Chemical Laser Amplifiers
FAN Anfu, GAO Zhi
Chin. Phys. Lett. 1991, 8 (11): 566-569 .  
Abstract   PDF(pc) (72KB) ( 469 )
We present "convection-nonequilibrium cross relaxation" model for a gas flow and chemical lasers, Teh experessions of the saturated gain spectrum are obtained for the two-type flow models with layer or turbulent flow mixture respectively. The numerical results show that the gain profile of a saturated amplifier with Doppler-broadening is a mixture of inhomogeneous and homogeneous profiles
Global Wave Solution of generalized MHD Equations in a Cylindrical Plasma
YANG Weihong, HU Xiwei
Chin. Phys. Lett. 1991, 8 (11): 570-573 .  
Abstract   PDF(pc) (78KB) ( 488 )
The linear eigenstate problem of generalized magnetohydrodynamics(MHD) equations in a cylindrical plasma is discussed. The effects of finite frequency and finite pressure perturbation lead to an important result: the resonant layer of the shear Alfven waves is not a singular layer. In this paper, the MHD equations are reduced to four differential equations of first order for perturbed quantities. An analytical dispersion relation for a homogeneous plasma cylinder is obtained. The K. Appert theory is a limiting case of our theory
Interference Diagnosis of the Initial Stage of Laser-Produced-Plasma in Air
HE Anzhi, LU Jian, NI Xiaowu
Chin. Phys. Lett. 1991, 8 (11): 574-577 .  
Abstract   PDF(pc) (120KB) ( 427 )
By using a Q-switched YAG Laser and a optical path delay set-up, we study the process in whith a laser induces breakdown to produce plasma in air, and obtain time-resolved Mach-Zehnder interferograms and optical shadowgrams of the initial stage of the plasma and the expansion wave produced in the process for the first time
Phonons in Excited State for Polydiacetylene
PENG Jingcui
Chin. Phys. Lett. 1991, 8 (11): 578-580 .  
Abstract   PDF(pc) (84KB) ( 425 )
A simple model is used to evaluate the phonon frequencies in both ground and excited state for polydiacetylene. The spring constants Kσi in the σ-bond skeleton are distinct from the experimental effective spring constants Ki. The results are compared with experimental date.
Optical-Phonon Deformation Potentials in Diamond-structure crystals: ab initio LMTO-ASA Calculation
KE Sanhuang, WANG Renzhi, HUANG Meichun
Chin. Phys. Lett. 1991, 8 (11): 581-584 .  
Abstract   PDF(pc) (104KB) ( 453 )
The optical-phonon deformation potentials of C, Si, Ge and Sn are calculated by LMTO-ASA approach within the frozen-phonon approximation. The comparisons between our results and those of several present theoretical calculations and experiments demonstrate that our calculation model is reasonable
Memory Effect in Ceramic Superconductors
JIN Xin, ZHANG Yitong, YAN Yong, JI Helin
Chin. Phys. Lett. 1991, 8 (11): 585-588 .  
Abstract   PDF(pc) (118KB) ( 464 )
We measured the time decay of the magnetic moment of high Tc superconductors YBa2Cu3O7-δ ceramic samples and found the memory effect which has hitherto been reported only in single crystals. The temperature and field ranges, especially the memory phenomenon in ceramic samples at liquid nitrogen temperature can only be understood in a combined picture of both flux creep and glass behaviour
Intercalation Reaction of Bi2(Sr,Nd)2CuOyBi2Sr2(Ca,Gd)Cu2Oy and Related Compounds with Iodine
CHEN Zuyao, GU Zhengtian, QIAN Yitai, WANG Xiqin
Chin. Phys. Lett. 1991, 8 (11): 589-592 .  
Abstract   PDF(pc) (104KB) ( 415 )
With iodine vapour treatment of various single crystals of Bi-Sr-Ca-Ln(Rare earch element)-Cu-O system, the stage-1 iodine-intercalation compounds of Bi2(Sr,Nd)2CuOy(2201), Bi2Sr2(Ca,Gd)Cu2Oy or Bi2Sr2CaCu2Oy(2212) and Bi8SrCaO14 have been prepared. x-ray diffraction and transmission electron microscope analysis indicate that iodine layer of thickness 3.2~3.5Å is formed between two Bi2-O2
Nonlinear Dispersion of Magnetostatic Surface Waves on Ferromagnetic Films
A.D.Boardman, BAO Jiashan, Wang Qi, CAI Yingshi, S.A.Nikitov
Chin. Phys. Lett. 1991, 8 (11): 593-596 .  
Abstract   PDF(pc) (71KB) ( 457 )
The wave equation of nonlinear magnetostatic surface waves (MSSW) on ferromagnetic films is derived and its solution is found. The nonlinear dispersion relation of MSSW in discussed. Our Result shows that the wave power has a little effect to the frequency shift of MSSW with lower frequency, but has a considerably larger effect to that with higher frequency within the band.
Influence of the Heat Treatment Duration on the Critical Temperature for the Break-Down of Vertical Bloch Line Chains
HAN BaoShan, R.Dahlbeck, Yuan Yuling, J.Engemann
Chin. Phys. Lett. 1991, 8 (11): 597-599 .  
Abstract   PDF(pc) (78KB) ( 539 )
For longer heat treatment duration(10 and 30 min), near and within the transition region, the softening fraction ρ has an obvious, but not very large increase and the increment for 30 min is greater than that for 10 min. As a result, the critical temperature T0 is only lowered by 2~3°C for a typical sample. The above results indicate the existence of a quasi-static athermal instability, and the thermal activation of Bloch points is only of secondary importance.
On the Optical Properties in Nesting Fermi Liquid
Li Meihua, TIAN Shiyang, ZHAO Zhongxian
Chin. Phys. Lett. 1991, 8 (11): 600-602 .  
Abstract   PDF(pc) (73KB) ( 472 )
One of the most common and prominent optical features of high temperture supeconductors is the quadratic frequence of the loss function, i.e., Im(-1/ε)=βω2, for ħω ≤1eV.We show that the nesting Fermi liquid (NFL) theory can quantitatively account for the low frequency(<0.5eV) behavior, but it can not explain the higher frequency behavior. This suggests that the form of relaxation rate derived from the NFL is inadequate to describe the high frequency behavior in high temperature superconductors
Langmuir-Blodgett Films with Bilayer Alternation of Hemicyanine Dye and Cadmium Stearate
J.Y.Fang, Z.M.Sun, S.J.Xiao, Z.H.Lu, Y.Wei, P.Stroeve
Chin. Phys. Lett. 1991, 8 (11): 603-606 .  
Abstract   PDF(pc) (94KB) ( 366 )
Multilayers consisting of bilayer alternation of hemicyanine dye and cadmium stearate have been prepared by the Langmuir-Blodgett technique. x-ray diffraction and optical absorption spectra are used to characterize their periodic structures and optical properties. The results show that a well ordered supperlattic is produced and the hemicyanine dye is in non-aggregated formation in the alternating multilayers.
15 articles