作者机构：
[Li, GX] Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.;Queens Univ Belfast, Dept Appl Math & Theoret Phys, Belfast BT7 1NN, Antrim, North Ireland.
通讯机构：
[Li, GX] H;Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
关键词：
光化电离系统;自电离态;相干群陷阱作用
摘要：
We investigate the atomic coherent population trapping in the system of two-mode quantized field interacting with a Λ-configuration atom with two lower bound states, one autoionizing state and a flat atomic continuum. The states of the field which traps the atom in its two lower bound states are given and the influence of the field induced continuum structure is examined.
期刊：
EUROPEAN PHYSICAL JOURNAL B,1997年102(2):233-237 ISSN：1434-6028
通讯作者：
Li, GX
作者机构：
[Peng, JS; Li, GX] HUAZHONG NORMAL UNIV, DEPT PHYS, WUHAN 430070, PEOPLES R CHINA.;[Li, GX] CHINA CTR ADV SCI & TECHNOL, WORLD LAB, POB 8730, BEIJING 100080, PEOPLES R CHINA.
通讯机构：
[Li, GX] C;CHINA CTR ADV SCI & TECHNOL, WORLD LAB, POB 8730, BEIJING 100080, PEOPLES R CHINA.
摘要：
The atomic coherent population trapping in the system of an atom with one ground state, a pair of excited states and a set of continuum states, interacting with two temporally separated sets of laser pulses with different phases is investigated. The relative phases of laser pulses on the amount of atomic populations trapped in the three bound states and the efficiency of population transfer are analyzed.
作者机构：
[Wiedemann, U.A.] Inst. für Theoretische Physik, Universität Regensburg, D-93040 Regensburg, Germany;Faculty of Mathematics and Physics, Comenius University, Mlynská Dolina, SK-84215 Bratislava, Slovakia;CERN, Theory Division, CH-1211 Geneve, Switzerland;Institute of Particle Physics, Hua-Zhong Normal University, Wuhan, China;[Heinz, U.] Inst. für Theoretische Physik, Universität Regensburg, D-93040 Regensburg, Germany, CERN, Theory Division, CH-1211 Geneve, Switzerland
通讯机构：
[Tomášik, B.] I;Inst. für Theoretische Physik, Universität Regensburg, Germany
摘要：
We present the Yano-Koonin-Podgoretskiǐ parametrisation of the correlation function. Compared to the conventionally used Cartesian parametrisation, this one provides more straightforward measurement of the duration of the emission process in the fireball and a clearer signal of the longitudinal expansion, which is expected in ulrarelativistic heavy ion collisions.
作者机构：
ACAD SINICA, INST HIGH ENERGY PHYS, BEIJING, PEOPLES R CHINA.;INST GRAVITAT & SPACE RES, BUCHAREST, ROMANIA.;PANJAB UNIV, DEPT PHYS, CHANDIGARH 160014, INDIA.;HUNAN EDUC INST, DEPT PHYS, CHANGSHA, HUNAN, PEOPLES R CHINA.;JOINT INST NUCL RES DUBNA, LAB HIGH ENERGIES, DUBNA, RUSSIA.
通讯机构：
[Adamovich, MI] I;INST HIGH ENERGY PHYS, ALMATY, KAZAKHSTAN.
摘要：
Angular distributions of projectile-associated He fragments from Pb induced reactions on stationary Pb target at 158 A GeV/c incident momentum are reported. The precision of the angular measurements was about ±0.01 mrad. Two emission components are appearing in the projected angular spectra of the He particles, one representing fragmentation at Fermi momentum scale, while the other one exhibits large transverse momentum transfer. By scaling with the incident momentum the angular spectra of He particles are compared with earlier reported measurements of Au on Au interactions at 11.6 A GeV/c. The pT spectrum of the He particles appears the same for the two cases.
作者机构：
HUAZHONG NORMAL UNIV, INST PARTICLE PHYS, WUHAN 430070, PEOPLES R CHINA.;CHINA CTR ADV SCI & TECHNOL, WORLD LAB, BEIJING 100080, PEOPLES R CHINA.;[Jia, Y] HUAZHONG NORMAL UNIV, DEPT PHYS, WUHAN 430070, PEOPLES R CHINA.
通讯机构：
[Jia, Y] H;HUAZHONG NORMAL UNIV, DEPT PHYS, WUHAN 430070, PEOPLES R CHINA.
摘要：
In this Letter we discuss a bistable model driven by two white noise sources, when the correlation time of the correlations between two sources τ is nonzero. We find that there is a critical value of the correlation time τc. For τ>τc, the system undergoes a succession of two phase transitions (namely, the reentrance phenomenon) as the strength of the correlations between two noise sources λ is varied. However, for τ<τc, the system undergoes a (single) phase transition as λ is varied.
摘要：
With asymptotic method developed from weak turbulent theory, the kinetic equations for QGP are expanded in fluctuation field potential A(mu)(T). Considering the second-order and third-order currents, we derive the nonlinear permeability tensor function from Yang-Mills field equation, and find that the third-order current is more important in turbulent theory. The nonlinear permeability formulae for longitudinal color oscillations show that the non-Abelian effects are more important than the Abelian-like effects. To compare with other works, we give the numerical result of the damping rate for the modes with zero wave vector. (C) 1997 Elsevier Science B.V.
期刊：
JOURNAL OF PHYSICS-CONDENSED MATTER,1997年9(23):4925-4930 ISSN：0953-8984
作者机构：
CENT CHINA NORMAL UNIV,DEPT PHYS,WUHAN 430070,HUBEI,PEOPLES R CHINA.;ACAD SINICA,INT CTR MAT PHYS,SHENYANG 110015,PEOPLES R CHINA.;NANJING UNIV SCI & TECHNOL,DEPT APPL PHYS,NANJING 210014,PEOPLES R CHINA.;UNIV SCI & TECHNOL CHINA,CTR FUNDAMENTAL PHYS,HEFEI 230026,ANHUI,PEOPLES R CHINA.;CENT CHINA NORMAL UNIV,DEPT PHYS,WUHAN,HUBEI,PEOPLES R CHINA.
摘要：
The magnetic properties of icosahedral MRu12 clusters are studied using the discrete-variational local-spin-density-functional method, where M = V, Cr, Mn, Fe, Co, and Ni. The results show that all of the I-h MRu12 clusters, just like the case for the I-h Ru-13 cluster, have double magnetic solutions. In contrast to the moment of 4 mu(B) for the I-h Ru-13 cluster, the total magnetic moments of the I-h MRu12 clusters, ranging from 1 mu(B) to 20 mu B, have been changed greatly by the substitution of the central Ru atom with M. Among them, the NiRu12 cluster has a giant moment of 20 mu(B). Furthermore, the NiRu12 cluster has nondegenerate ground state and could be expected to be remarkably stable. Therefore, for the purpose of enhancing the magnetic moment of the I-h Ru-13 cluster, Ni is a promising candidate as a dopant. Finally, we predict that all the I-h MRu12 clusters except NiRu12 might belong to the class in which the magnetization of the cluster increases with temperature.
