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Volume 4 Issue 8
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Original Articles
A NEW METHOD FOR INVERSE BLACK BODY RADIATION PROBLEM
CHEN Nanxian
Chin. Phys. Lett. 1987, 4 (8): 337-340 .  
Abstract   PDF(pc) (45KB) ( 354 )
A completely new method is presented to solve the inverse black body radiation problem. The solution makes use of the widely known and easily implemented Fourier transform, and the expression is very simple and clear. This method is of major significance with respect not only to the numerical computation, but also to uniqueness or existence of this problem. At the same time, this method is also very useful for many other fields.
TOTAL ABSORPTION AND EMISSION PROBABILITIES IN HOT NUCLEI
WU Shishu
Chin. Phys. Lett. 1987, 4 (8): 341-344 .  
Abstract   PDF(pc) (49KB) ( 440 )
A general relation between the total absorption and emission probabilities for nuclei in thermal equilibrium at a finite temperature is derived, and its relevance to giant resonances built on nuclear excited states discussed.
C2 SWAN BAND EMISSION BY MULTIPHOTON PHOTODISSOCIATION OF C4H2N2 MOLECULE AT 193nm
XIE Xiaoxiang*, J.B. Halpern**, W.M. Jackson
Chin. Phys. Lett. 1987, 4 (8): 345-348 .  
Abstract   PDF(pc) (60KB) ( 428 )
Multiphoton dissociation of C4H2N2 molecules at 193nm has been studied at high laser intensities. Emission spectra are recorded from violet (B 2Σ →X 2Σ) bands of CN and the Swan bands of C2 (d 3πg a 3πu).

NEW LOCALIZED ELECTRONIC STATES OF SOLITON IN TRANS-(CH)x
FU Rouli*, XIE Shijie**, WU Changqin, SUN Xin
Chin. Phys. Lett. 1987, 4 (8): 349-352 .  
Abstract   PDF(pc) (48KB) ( 782 )
It is well known that the soliton in trans-(CH)x possesses a localized electronic state at the center of the gap. Besides this mid-gap state, we have found that there exist another four localized electronic states around the soliton. They form four discrete levels outside the conduction and valence bands: one sits near the bottom edge of the conduction band and one near the top edge of the conduction band; another two are located symmetrically near the valence band.
THE MAGNETIC SINGLE-ION ANISOTROPY IN HEMATITE
LI Hua, JIANG Shouting, ME Liangmo, KUO Yicheng, YANG Gueilin*, XU You*, ZHAI Hongru*
Chin. Phys. Lett. 1987, 4 (8): 353-356 .  
Abstract   PDF(pc) (46KB) ( 416 )
A calculation of the magnetic single-ion anisotropy in hematite has been made. The results show that an equivalent single-ion anisotropy field Hsi(=103.8x102 Oe) exists along the c-axis at T=0K. The Morin transition in hematite could be explained by our results in conjunction with the calculated Hmd by Artman et al.

X-RAY DIFFRACTION STUDY OF ICOSAHEDRAL PHASE IN RAPIDLY QUENCHED A1-Mn
JIANG Xiaoming, HUANG Yunlan, WU Ziqin
Chin. Phys. Lett. 1987, 4 (8): 357-360 .  
Abstract   PDF(pc) (53KB) ( 414 )
Variation of the correlation length of icosahedral phase with the annealing temperature is got according to the broadening of the X-ray diffraction peak. The fact that the correlation length does not change during the crystallization process means that the grains of icosahedral phase are transformed wholly and perfectly to crystalline Al6Mn.
DIFFUSION-LIMITED AGGREGATION WITH LONG-RANGE FORCE
HIUANG Yun*, LIU Jiagang**, WANG Liangru, ZHAO Huimin
Chin. Phys. Lett. 1987, 4 (8): 361-364 .  
Abstract   PDF(pc) (71KB) ( 451 )
The diffusion-limited aggregation model with long-range force is investigated. Single particles are moving under the control of Brownian motion and drift motion produced by regular centrical long-range force. The computer simulations under this condition have been studied in detail in two dimensions, and the results are compared with the properly electrolytic deposition experiments.
WEAK LOCALIZATION IN THIN Cu FILMS WITH SMALL AMOUNTS OF La, Ce ADDITIVES
YAN Shousheng, WANG Qi, YE Zhiyuan, ZHAO Yancheng, ZHAO Wei, ZHANG Xinmin*
Chin. Phys. Lett. 1987, 4 (8): 365-368 .  
Abstract   PDF(pc) (48KB) ( 416 )
Resistance measurements at between 1.5 to 40K and Magnetoconductance measurements at about 1.5K have been made on l00Å Cu films, and also on Cu films with small amounts of La, Ce additives. The Ce atoms in Cu seem to give much stronger spin-orbit scattering than La atoms do. The behaviour of the Cu film with Ce additives is a composite of weak localization and Kondo effect.
STUDIES OF ALL-NIOBIUM ELECTRODE JOSEPHSON TUNNEL JUNCTIONS WITH AMORPHOPUS SILICON BARRIERS
MENG Xiaofan, WANG Xiewen
Chin. Phys. Lett. 1987, 4 (8): 369-372 .  
Abstract   PDF(pc) (67KB) ( 402 )
This paper reports the fabrication and properties of small Nb--( a-Si )-Nb-(a-Si)-Nb Josephson tunnel junctions. The smallest junction area is about 0.3μm2. A thin a-Si film deposited by electron beam evaporation was oxidized and used for the tunnel barriers. TEM and XPS investigations indicate that the barrier layers consist of SiOx and Si. The junctions have been used for RF SQUID with an energy resolution of 1.9 x l0-28 J/Hz.

EFFECT ON TRANSPORT PROPERTIES OF ELECTRONS AT MODULATION-DOPED GaAs/AlGaAs HETEROSTRUCTURE INTERFACE BY NEUTRON IRRADIATION
WU Yongsheng, HUANG Yi, ZHOU Junming, MENG Xiangti*
Chin. Phys. Lett. 1987, 4 (8): 373-376 .  
Abstract   PDF(pc) (58KB) ( 398 )
It has been found that after the irradiation by fast neutrons the electron density and mobility of two-dimensional (2D) electron gas at modulation-doped GaAs/AlGaAs heterostructure interface increased by 17% and 23%, respectively, and the Hall plateaus and the minima of Shubnikov-de Haas (S-dH) oscillation curves anomalously shifted over each other. The measurements after three weeks showed that the effects mentioned above had disappeared substantially, however, the stronger persistent photoconductivity still remained.
A LARGE CP VIOLATION EFFECT IN THE Bs- Bs SYSTEM
DU Dongsheng, WU Dandi, Isard Dunietz
Chin. Phys. Lett. 1987, 4 (8): 377-380 .  
Abstract   PDF(pc) (50KB) ( 401 )
The CP violation in Bs →F±Fis of the order 0( 0.1) due to the interplay of mixing and interference. The event rate is about 10-5, if C=+ for the primary BsBs pair .
ON GAUGE COVARIANT FORMULATION OF STRING FIELD THEORIES II
TANG Jufei, ZHU Chuanjie
Chin. Phys. Lett. 1987, 4 (8): 381-383 .  
Abstract   PDF(pc) (33KB) ( 329 )
The rules of truncation for getting a gauge invariant action from a gauge-fixed action are put forward and completed. It is shown that the presently well-known gauge invariant action (ψ |QB|ψ ) can also be obtained by means of truncaton. The confusion of considering this action as a gauge-fixed action is clarified.

12 articles