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Volume 4 Issue 3
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Original Articles
STUDY ON SUPERCONDUCTIVITY OF AlSi ALLOY USING ION BEAM MIXING
XI Xiaoxing*, RAN Qize, NI Yongming, LIU Jiarui, GUAN Weiyan
Chin. Phys. Lett. 1987, 4 (3): 97-100 .  
Abstract   PDF(pc) (40KB) ( 440 )
Ion beam mixing is conducted at liquid helium temperature to study the superconductivity of AlSi alloy (Al -21.8at%Si). Along with the process of transforming from multilayer structure to a uniform Al and Si alloy, the superconducting properties are continuously improved. The highest Tc obtained is 6.84K.
NEAR LINEAR TEMPERATURE DEPENDENCE OF THE THERMPOWER IN AMOPHOUS FeMnB ALLOYS
YAN Shousheng, REN Jie, LI Dongqi, TONG Litai
Chin. Phys. Lett. 1987, 4 (3): 101-104 .  
Abstract   PDF(pc) (45KB) ( 398 )
The near linear temperature dependence of the thermopower in magnetic amorphous FeMnB alloys over a wide temperature range is reported. It is due to the weakened magnetic extra contribution to the thermopower, when enough Fe atoms were replaced by Mn, whose contribution is opposite to that of the host. In this situation, using a two-component model, as an extreme simplication of the Feber-Ziman theory of liquid metal, it is able to explain the composition dependence of the thermopower.
NEUTRON DIFFRACTION STUDY OF α-IRON TITANIUM CERIUM HYDRIDE
LIN Hong*, NIU Shiwen*, GOU Cheng*, JIN Longhuan**, TAO Fang**, BAO Deyou, SU Lanying
Chin. Phys. Lett. 1987, 4 (3): 105-108 .  
Abstract   PDF(pc) (47KB) ( 474 )
The results of the neutron scattering method shows that the crystal structure of Fe0.94TiCe0.06H0.03 is the same as that of the FeTiH0.02. However, its diffraction peak intensities drop by 47-58%, the background increased markedly about 2 times and the lattice constant increase by 5%.
PERSISTENT PHOTOCONDUCTIVITY IN UNDOPED a-Si:H/a-Si1-xCx :H MULTILAYERS
XU Xixiang, ZHANG Fangqing, CHEN Guanghua
Chin. Phys. Lett. 1987, 4 (3): 109-112 .  
Abstract   PDF(pc) (44KB) ( 394 )
Persistent photoconductivity(PPC) effect is first observed at room temperature in undoped a-Si:H/a-Si1-xCx:H multilayers. The origin of PPC effect and related experimental results in our case are pre-liminarily discussed.
RECOVERY OF THE INTENSITY ENVELOPE OF AN ULTRASHORT LASER PULSE FROM EXPERIMENTAL CORRELATION DATA
ZHU Zhenhe
Chin. Phys. Lett. 1987, 4 (3): 113-116 .  
Abstract   PDF(pc) (41KB) ( 374 )
It is shown that the time-dependent intensity of an ultrashort laser pulse can be recovered from the second-order correlation G(2)( τ ) and the third-order correlation with single time-delay G(3)( τ ) . The recovery is successfully carried out by a computer with ingenious programming.
MICROSCOPIC RELATIVISTIC DESCRIPTION OF OPTICAL MODEL POTENTIAL
MA Zhongyu, ZHU Ping, GU Yingqi, ZHUO Yizhong
Chin. Phys. Lett. 1987, 4 (3): 117-120 .  
Abstract   PDF(pc) (46KB) ( 457 )
The microscopic relativistic optical potentials in energy region of E<300MeV have been studied and calculated. An effective Lagrangian density with two adjustable coupling constants (gσ, gω) is chosen by reproducing the bulk properties of nuclear matter in the Dirac-Hartree-Fock (DHF) approximation. It is found that the optical potential calculated in this model is in good agreement with those obtained by phenomenological fitting up to the energy of 300MeV.
SIMULATION OF THE RADIAL TRANSPORT IN CT-6B TOKAMAK DURING GAS PUFFING
LIU Min, WANG Long, LIN Ruiyan
Chin. Phys. Lett. 1987, 4 (3): 121-124 .  
Abstract   PDF(pc) (48KB) ( 364 )
A parameter evolution in CT-6B tokamak during gas puffing is numerically studied using a one-dimensional tokamak transport code. The calculated results show that the gas puffing enhances the average electron density. The transport coefficients obtained from the simulation are compared with those from the measurements performed on CT-6B device.
THE DRIFT CYCLOTRON LOSS-CONE INSTABILITIES IN AN INHOMOGENEOUS MAGNETIC FIELD
GUO Shichong, SHEN Jiewu, CAI Shitong ( S . T . Tsai )
Chin. Phys. Lett. 1987, 4 (3): 125-128 .  
Abstract   PDF(pc) (51KB) ( 348 )
The effects of kinetic pole on drift cyclotron loss-cone instability are studied in detail, especially for the ▽B-drift resonance contribution. It is found that the kinetic resonance acts as dissipative effect which can enhance the instability and broaden the unstable region of negative energy DCLC mode.
HYBRID OPTICAL BISTABILITY IN FABRY-PEROT INTERFEROMETER CONTAINING PLASMA
ZHONG Quande
Chin. Phys. Lett. 1987, 4 (3): 129-132 .  
Abstract   PDF(pc) (45KB) ( 342 )
A hybrid optical bistable system of a plasma in a Fabry-Perot interferometer driven by a single-mode cw laser is proposed. The general expressions of the minimum change of the electron density for optical bistability and the changes of electron density at the "on" and "off” points of the optical bistability are obtained theoretically. The necessary data for the design of the optical bistability in infrared to mm-wave region are given.
FIRST SUBHARMONIC OF SOUND IN DISTURBED WATER
SHAO Daoyuan, QIAN Zuwen
Chin. Phys. Lett. 1987, 4 (3): 133-135 .  
Abstract   PDF(pc) (49KB) ( 455 )
It is shown by this experiment that an appreciable first subharmonic component (one-half of driving frequency) can be observed when a travelling wave of low-intensity sound goes through the disturbed water in a tank.
THE MONOPOLE PROBLEM AND THE PRIMORDEAL BLACK HOLE PROBLEM IN THE INFLATIONARY UNIVERSE
LIU Liao
Chin. Phys. Lett. 1987, 4 (3): 136-138 .  
Abstract   PDF(pc) (34KB) ( 437 )
By considering the non-uniform phase transition, a theoretical lower bound of the probability of finding the 't Hooft-Polyakov monopole in the so-called Inflationary universe is given.
THE ELECTRIC MONOPOLE IN KALUZA-KLEIN THEORY
TANG Jufei, ZHU Chuanjie
Chin. Phys. Lett. 1987, 4 (3): 139-141 .  
Abstract   PDF(pc) (30KB) ( 481 )
We have completely integrated out the field equations to obtain all spherically symmetric electric monopole solutions in the five dimensional Kaluza-Klein theory. A specific solution is given and its relevance to the classical theory of electron is discussed.
A LOW-ENERGY PHOTOLUMINESCENCE PEAK IN a-Si:H FILMS
MA Honglei, CAO Baocheng, LOU Wenxiu, YE Yagu*
Chin. Phys. Lett. 1987, 4 (3): 142-144 .  
Abstract   PDF(pc) (40KB) ( 444 )
A 0.65-0.70eV luminescence peak in a-Si:H films after illumination is reported. It is found that exposure to light decreases total integrated intensity of luminescence and also produces two luminescence peaks, one is in the range 0.80-0.90eV, and the other is in 0.65-0.70eV. The former disapears by annealing at 190°C, but the latter can not be removed. Similar luminescence peaks are observed in a-Si:H films prepared under higher RF power without illumination.
13 articles