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Volume 2 Issue 11
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Original Articles
NMR STUDIES ON LiKSO4 DOWN TO LIQUID HELIUM TEMPERATURE
MENG Qing-an, CAO Qi-juan, LI Zi-rong
Chin. Phys. Lett. 1985, 2 (11): 481-484 .  
Abstract   PDF(pc) (49KB) ( 372 )
7Li NMR spectra of LiKSO4 single crystal have been observed from 100K down to liquid helium temperature. A structural phase transition was identified at about 40K, below which the unit cell of the crystal has at least 8 molecular formulas. At 4.2K the parameters for the electric field gradient (EFG) tensors at Li sites were obtained.
STUDIES ON SEMICONDUCTOR SURFACE PARAMETER BY USE OF SAW TECHNIQUE
WU Wen-qiu, QIN Xi
Chin. Phys. Lett. 1985, 2 (11): 485-488 .  
Abstract   PDF(pc) (42KB) ( 365 )
Using the concepts of continuity of interface impedance, the changes of both the velocity and attenuation of surface acoustic wave (SAW) caused by acousto-electric interaction are considered layer by lager under different semicon-ductor surface conditions for the piezoelectric-insulator-semiconductor(PIS) structures. Surface densities of states and fixed charge densities are evaluated by computer fitting and the results agree well with those obtained by other methods.
THE Λ-PARAMETER AND DECONFINEMENT PHASE TRANSITION AT FINITE TEMPERATURES FOR SU(2) LATTICE GAUGE THEORY WITH EXP ACTION
DONG Shao-jing
Chin. Phys. Lett. 1985, 2 (11): 489-492 .  
Abstract   PDF(pc) (43KB) ( 590 )
The pure lattice SU(2) gauge theory is studied with a single plaquette EXP action by means of Monte Carlo simulations using a 120 element subgroup. The ratio of the lattice Λ-parameter to the square root of string tension is (1.02±0.05) x 10-4, which is much less than that of Wilson's action. But at finite temperatures, the deconfinement transition point is found to be TC = (210±28)MeV, in good agreement with Wilson's one.


IN SITU OBSERVATION OF THE H-INDUCED DEFECTS IN SILICON SINGLE CRYSTALS
MA Zhen-hong, W. Graeff*
Chin. Phys. Lett. 1985, 2 (11): 493-496 .  
Abstract   PDF(pc) (58KB) ( 407 )
The hydrogen-induced defects in FZ silicon grown in hydrogen atmosphere have been investigated by both the conventional and the in situ white beam synchrotron radiation topography. The formation process of the defects is discussed.
PERIOD-DOUBLING BIFURCATION FOR A DELAY-DIFFERENTIAL EQUATION RELATED TO OPTICAL BISTABILITY
LI Jia-nan
Chin. Phys. Lett. 1985, 2 (11): 497-500 .  
Abstract   PDF(pc) (33KB) ( 406 )
The bifurcation of a periodic solution for a delay differential equation related to optical bistability, has been discussed analytically. Using the theory of retarded functional differential equations, we have proved that it follows precisely the period-doubling route.
THE MEASUREMENT ON MAGNETOPHONON RESONANCE OF 2D ELECTRON SYSTEM IN GaAs-AlxGa1-xAs HETEROSTRUCTURE INTERFACE
WU Yong-sheng, HUANG Yi, YANG Fu-min, ZHAO Xi-chao, ZHOU Jun-ming
Chin. Phys. Lett. 1985, 2 (11): 501-504 .  
Abstract   PDF(pc) (51KB) ( 467 )
The 20 magnetophonon oscillatory in GaAs-AlxGa1-xAs hetero-structure interface, grown by MBE, has been investigated by means of the second derivative of the magnetoresistance under high pulsed magnetic fields up to 40T. The fundamental magnetic field has been measured as 23.7T and the damping facter γ , 2D electron effective mass m* for our sample are 1.58 and 0. 0747me, respectively.
NEUTRINOLESS DOUBLE BETA DECAY OF 48Ca AND THE MASS OF HEAVY MAJORANA NEUTRINO
WU Hui-fang
Chin. Phys. Lett. 1985, 2 (11): 505-508 .  
Abstract   PDF(pc) (47KB) ( 378 )
Neutrinoless double beta decay of 48Ca is discussed in the double charge exchange of pions in flight between two nucleons by using a diagrammatic effective operator approach. The virtual intermediate neutrino is assumed to be of the heavy Majorana type.
GAS VARIFOCAL LENS
XIE Bang-li, XIA Sheng-jie, CHOW Quan-tie
Chin. Phys. Lett. 1985, 2 (11): 509-512 .  
Abstract   PDF(pc) (52KB) ( 357 )
The stable laminar flow established by an air stream sucked through a heated tube acts as an optically thin lens with variable focal length depending on the dimensions of the tube, tube-temperature and flow velocity.
ASED-MO STUDY FOR THE COADSORPTION OF CO AND K ON Ni(100) SURFACE
CAO Pei-Lin, SHI Dan-hua
Chin. Phys. Lett. 1985, 2 (11): 513-516 .  
Abstract   PDF(pc) (51KB) ( 332 )
The interactions between CO and K on Ni(100) are studied using ASED-MO theory. The activation barrier for CO dissociation is greatly decreased in the presence of K, it is caused mainly by the direct local interaction between CO(2π) and K(4s). The long range interaction between CO and K through the electrons of the substrate surface enhance the binding energy of the molecularly adsorbed CO on this surface.

ONE POSSIBLE MECHANISM FOR CORIOLIS ATTENUATION
ZENG Jin-yan, CHENG Tan-sheng
Chin. Phys. Lett. 1985, 2 (11): 517-520 .  
Abstract   PDF(pc) (48KB) ( 390 )
The blocking effect on the nuclear pairing correlation in combination with some small change of the single-particle level scheme near the Fermi surface may lead to a Large Coriolis attenuation.
INTERNAL FRICTION, SHEAR MODULUS AND MAGNETIC SUSCEPTIBILITY OF LANTHANUM
LI Guang-yi, PAN Zheng-liang, WANG Xiao-wei, XIAO Jin-quan
Chin. Phys. Lett. 1985, 2 (11): 521-524 .  
Abstract   PDF(pc) (49KB) ( 400 )
The internal friction, relative shear modulus and magnetic susceptibility of La as a function of temperature have been observed in the range 80-700K. The mechanism of phase transformation FCC-double HCP of La is discussed.
DISTORTED KOSSEL DIFFRACTION OF LiNbO3 IN THE VICINITY OF 75°C
HAN Fu-sen*, ZHANG Jian-zhong, FAN De-pei
Chin. Phys. Lett. 1985, 2 (11): 525-527 .  
Abstract   PDF(pc) (31KB) ( 462 )
Some abnormal Kossel lines of pure LiNbO3 crystal have been observed in the vicinity of 75°C and in Ti-diffused one at wide temperature range. Reasonable explanation is that the diffraction plane inclines locally from its normal position at that temperature. A computer simulation has been made and shows an agreement with the calculations. The change of elastic constant or heat expansion coefficient etc. may be the cause of the deformation of the pure crystal near 75°C.
12 articles