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Volume 4 Issue 10
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Original Articles
BOLOMETRIC MEASUREMENT OF RESONANT SURFACE PLASMON EXCITATION AT A SILVER SURFACE
XIE Yuanlin, ZHOU Yueliang, YANG Guozhen, GU Shijie
Chin. Phys. Lett. 1987, 4 (10): 433-436 .  
Abstract   PDF(pc) (49KB) ( 414 )
A new method for measuring surface plasmon (SP) at a metal surface is presented. When exciting a surface plasmon at a metal surface, the metal film will be heated by SP, which leads to changes in its resistance; therefore, the dispersion of SP can be measured by this change. This method has several advantages: it is simpler, convenient, more sensitive and reliable than other known methods, and capable of using nonpolarized light.
SUPERCONDUCTIVITY IN THE NEW HIGH-TC SUPERCONDUCTORS RBa2Cu3O9-y(R=Y, Nd, Sm, Eu, Gd, Dy, Er, Tm, Yb)
TANG Huabin, REN Yang, LIU Yinglie, YAN Qiwei, ZHANG Zong, ZHENG Jiaqi, SHAO Xiuyu, DUAN Zhanguo
Chin. Phys. Lett. 1987, 4 (10): 437-440 .  
Abstract   PDF(pc) (51KB) ( 407 )
Superconductivities in the 90K range as measured by resistance and magnetic susceptibility are reported for RBa2Cu3O9-y(R=Y, Nd, Sm, Eu, Gd, Dy, Er, Tm, Yb) having the orthorhornbic perovskite structure. Unstable resistance drop above 100K has been found in ErBCO, probably associated with interfacial superconductivity.

CP VIOLATION IN THE STANDARD MODEL WITH FOUR GENERATIONS
WU Dandi, CERN-Geneva, WU Yueliang*
Chin. Phys. Lett. 1987, 4 (10): 441-444 .  
Abstract   PDF(pc) (43KB) ( 629 )
CP violation in the standard model with four generations of quarks in examined using rephasing invariants of the mixing matrix. A condition for CP invariance is presented and proved. CP violations in different sections are connected by orthogonal conditions.
A TENTATIVE MODEL FOR HIGH Tc Y-Ba-Cu-O SUPERCONDUCTORS FROM HREM STUDIES
HUA Zhongyi, CAI Yiming, QIU Jingwu, JIA Chunlin, MIAO Baicai, CHEN Kaiyuan, LUO Jian, OUYANG LU
Chin. Phys. Lett. 1987, 4 (10): 445-448 .  
Abstract   PDF(pc) (67KB) ( 404 )
A high Tc Y-Ba-Cu-O superconductor was prepared with a zero-resistance temperature at 89.9K. High resolution electron microscopy (HREM) indicates that the structure of this material is multiphase and looks like some insulating islands surrounded by regions of conductive phase. There exist many defects in the conductive phase which will be transformed into non-crystalline state after prolonged electron bombardment.
ACOUSTIC PLASMONS AND HEAVY-FERMION SUPERCONDUCTORS
XU Jihai
Chin. Phys. Lett. 1987, 4 (10): 449-452 .  
Abstract   PDF(pc) (38KB) ( 388 )
The acoustic Plasmons have been considered as a possible mechanism for superconductivity in heavy-fermion systems with s-and f-electons. This may be used to explain the exotic properties observed in heavy-fermion superconductors.
CRYSTAL STRUCTURE AND SUPERCONDUCTIVITY OF Ba2YCu3O9-x COMPOUND
CHE Guangcan, LIANG Jingkui, CHEN Wei, XIE Sishen YANG Qiansheng, CHEN Genghua, NI Youngming, LIU Guirong
Chin. Phys. Lett. 1987, 4 (10): 453-456 .  
Abstract   PDF(pc) (38KB) ( 456 )
The crystal structure and superconductivity of the compound Ba2YCu3O9-x are orted in this paper. The compound has an orthorhombic distorted perovskite structure cell with a=3.892Å, b=3.824Å and c=11.64Å. The temperature at the middle point of superconducting transition is 93.6K.
MULTI-MODE AND CHAOTIC OSCILLATIONS IN A NONLINEAR SYSTEM OF ACOUSTIC HYBRID WITH SINGLE PEAK FREQUENCY RESPONSE
MIAO Guoqing, WANG Benren, WEI Rongjue
Chin. Phys. Lett. 1987, 4 (10): 457-460 .  
Abstract   PDF(pc) (51KB) ( 669 )
Multi-mode and chaotic oscillations have been observed in an acoustic hybrid system with single peak frequency response and time-delay. The envelope of the frequency spectrum, as constrained by the frequency response, is comb-shaped. The numerical calculations show approximate agreement with the experimental result.
GENERATION AND MAINTENANCE OF A FIELD REVERSED CONFIGURATION BY MEANS OF A ROTATING MAGNETIC FIELD
A.Knight, WU Cheng, I.R.Jones
Chin. Phys. Lett. 1987, 4 (10): 461-464 .  
Abstract   PDF(pc) (58KB) ( 438 )
An experiment in which a rotating magnetic field was used to drive current in a cylindrical device was described. The driven current was of sufficient size to reverse the applied axial field. such an equilibrium could equally well be termed a field reversed configuration (FRC). In this experiment the FRC lifetime appeared to be limited by the duration of the rotating field pulse (40ms) with no evidence of gross instabilities.

A SIX-DIMENSIONAL COSMOLOGY SOLUTION WITH GUT AND MONOPOLE-INDUCED SPONTANEOUS COMPACTIFICATION
CAI Shengshan, HU Sizhu, LI Xinzhou, XU Jianjun
Chin. Phys. Lett. 1987, 4 (10): 465-468 .  
Abstract   PDF(pc) (42KB) ( 387 )
In this paper, the authors present a cosmological solution of a six-dimensional Einstein-gauge unification theory to which is added a matter term. This exact solution appears that cosmology of the very early universe may differ considerably from the usually contemplated "scenarios".
TDPAC STUDY ON ANNEALING BEHAVIOR OF In IN Si AFTER RECOIL IMPLANTATION
ZHU Shengyun, LI Donghong, LI Yuexin
Chin. Phys. Lett. 1987, 4 (10): 469-472 .  
Abstract   PDF(pc) (48KB) ( 430 )
Si wafer (N-type, P-doped, 1kΩ-cm) was implanted with 111In by nuclear reaction recoils. Thermal annealing behavior of In in Si was studied by the time differential perturbed angular correlation technique. It is found that after 798°C annealing 55% of the In atoms occupy substitutional lattice sites in Si with the remainder in perturbed sites.
NEW COSMOLOGICAL SOLUTIONS WITH Ads3x S1x S3x S3 COMPACTIFICATION OF SUPERSTRING
YAN Jun
Chin. Phys. Lett. 1987, 4 (10): 473-476 .  
Abstract   PDF(pc) (52KB) ( 414 )
We analysed d=10, 0(32) superstring theory with a cosmological constant for possible Kaluza-Klein cosmologies. In the former case (scalar field Ф=constant) we find an oscillating (2+l)-dimensional antide Sitter universe with a constant value for all fields on the internal dimensions, which are S1x S3x S3. In the latter case, it is not possible to get. a power law form solutions. In the oscillating solutions the induced cosmological constant is less than 10-120Mp-4 calculated according to supergravity theories.


PHOTOREFLECTANCE STUDY OF GaAs/AlGaAs MULTI-QUANTUM WELLS
TANG Yinsheng*, JIANG Desheng, ZHUANG Weihua, CHEN Zhonggui
Chin. Phys. Lett. 1987, 4 (10): 477-479 .  
Abstract   PDF(pc) (48KB) ( 452 )
Using photoreflectance (PR) at room temperature, we have studied GaAs/AlGaAs multi-quantum wells(MQWs) grown by molecular beam epitaxy. Analysis shows that the modulation mechanism of PR of MQWs is Stark shift of the subbands produced by photo-injection of carriers, which has first derivative functional lineshapes. By fitting the experimental spectra, an unusual transition coming from the interfaces in MQWs was observed.
12 articles