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Frontiers of Physics 第4卷第1期（2009）已经出版，网络版请浏览
期待国内外物理学家不吝赐稿（综述或研究论文、快讯，英文版，篇幅不限，免一切费用）！
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Frontiers of Physics
Volume 4 ■ Number 1 ■ 2009
Cover illustration
The BES-III (Beijing Sprectrometer III) detector, a general purpose solenoidal high performance detector located at the Beijing Electron-Positron Collider (BEPC-II), is designed to study the tau-charm physics at the center of mass energy of 2.0 to 4.6 GeV. It is 11 m long, 6 m wide, 9 m high and a total weight of about 700 ton, and consists of a drift chamber (MDC) which has a small cell structure filled with a helium-based gas, an electromagnetic calorimeter (EMC) made of CsI(Tl) crystals, time-of-flight counters (TOF) for particle identification made of plastic scintillators, a muon system made of Resistive Plate Chambers (RPC) and a super conducting magnet. The detector was finally installed into the assigned position in 2008 and has already been operated to collect data. The cover image shows the cross-section of BES-III. Please refer to the article “Charm physics — A field full of challenges and opportunities” by Professor Xue-qian LI et al. in this issue for details.
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Atomic, Molecular, and Optical Physics
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Strongly interacting ultracold quantum gases
Hui ZHAI (翟荟)1,2,3,4
1 Center for Advanced Study, Tsinghua University, Beijing 100084, China
2 Department of Physics, Ohio-State University, Columbus, Ohio, 43210, USA
3 Material Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
4 Department of Physics, University of California at Berkeley, Berkeley, CA, 94720, USA
This article reviews recent progresses in ultracold quantum gases, and it includes three subjects which are Fermi gases across a Feshbach resonance, quantum gases in the optical lattices and the fast rotating quantum gases. In this article, we discuss many basic physics pictures and concepts in quantum gases, for examples, the resonant interaction, universality and condensation in the lowest Landau level; we introduce fundamental theoretical tools for studying these systems, such as mean-field theory for BEC-BCS crossover and for boson Hubbard model; and we emphasize the important
unsolved problems in the forefront of this field, for instance, the temperature effect in optical lattices.
pp 1―20
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Cavity quantum networks for quantum information processing in decoherence-free subspace
Hua WEI (魏华)1,2 ( * ), Zhi-jiao DENG (邓志娇)1,3, Wan-li YANG (杨万里)1, Fei ZHOU (周飞)1
1State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
2Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
3Department of Physics, National University of Defense Technology, Changsha 410073, China
E-mail: huawei.hw@gmail.com
We give a brief review on the quantum information processing in decoherence-free subspace (DFS). We show how to realize the initialization of the entangled quantum states, information transfer and teleportation of quantum states, two-qubit Grover search and how to construct the quantum network in DFS, within the cavity QED regime based on a cavity-assisted interaction by single-photon pulses.
pp 21―37
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Quantum information density and network
Qiao BI (毕桥)1,3 ( * ), Jin-qing FANG (方锦清)2,3, Gui-ping LIU (刘桂平)1,3
1 Department of Physics, Science School, Wuhan University of Technology, Wuhan 430070,China
2 China Institute of Atomic Energy, P.O. Box 275-27, Beijng 102413, China
3 International Noble Academy,43-1075 Ellesmere Rd. Toronto, Ontario, Canada M1P 5C3
E-mail: biqiao@gmail.com
We present a quantum information network in which quantum information density is used for performing quantum computing or teleportation. The photons are entangled in quantum channels and play a role of flying ebit to transmit interaction among the nodes. A particular quantum Gaussian channel is constructed; it permits photon-encoded information to transmit quantum signals with certain quantum parallelism. The corresponding quantum dynamical mutual information is discussed, and the controlling nodes connectivity by driving the network is studied. With regard to different driving functions, the connectivity distribution of the network is complicated. They obey positive or negative power law, and also influence the assortativity coefficient or the dynamical property of the network.
pp 38―48
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Particles, Fields, Cosmology, and Astrophysics
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Charm physics − A field full of challenges and opportunities
Xue-qian LI (李学潜)1 ( * ), Xiang LIU (刘翔)2, Zheng-tao WEI (魏正涛)1
1 Department of Physics, Nankai University, Tianjin 300071, China
2 Centro de Fisica Computacional, Departamento de Fisica, Universidade de Coimbra, P-3004-516, Coimbra, Portugal
E-mail: lixq@nankai.edu.cn
In this review, we discuss some interesting issues in charm physics, which is full of puzzles and challenges. So far in this field, there exist many problems which have not obtained satisfactory answers yet as more unexpected phenomena Continue to be observed at the current facilities of high energy physics.
pp 49―74
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Models of G time variations in diverse dimensions
Vitaly N. MELNIKOV1,2
1 Center for Gravitation and Fundamental Metrology, VNIIMS, 46 Ozyornaya Str., Moscow 119361, Russia
2 Institute of Gravitation and Cosmology, People's Friendship University of Russia, 6 Mikhlukho-Maklaya Str., Moscow 117198, Russia
E-mail: melnikov@phys.msu.ru, melnikov@vniims.ru
A review of different cosmological models in diverse dimensions leading to a relatively small time variation of the effective gravitational constant G is presented. Among them: 4-dimensional general scalar-tensor model, multidimensional vacuum model with two curved Einstein spaces, multidimensional model with multicomponent anisotropic “perfect fluid”, S-brane model with scalar fields and two form field etc. It is shown, that there exist different possible ways of explanation of relatively small time variation of the effective gravitational constant G compatible with present cosmological data (e.g. acceleration): 4-dimensional scalar-tensor theories or multidimensional cosmological models with different matter sources. The experimental bounds on ˙G may be satisfied ether in some restricted interval or for all allowed valuesof the synchronous time variable.
pp 75―93
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The thermodynamics in a dynamical black hole
Bo LIU (刘博) , Wen-biao LIU (刘文彪) ( * )
Department of Physics, Institute of Theoretical Physics, Beijing Normal University, Beijing 100875, China
Considering the back-reaction of emitting particles to the black hole, a “new” horizon is suggested where thermodynamics can be built in the dynamical black hole. It, at least, means that the thermodynamics of a dynamical black hole should not be constructed at the original event horizon any more. The temperature, “new” horizon position and radiating particles’ energy will be consistent again under the theory of equilibrium thermodynamical system.
pp 94―96
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Statistical and Nonlinear Physics, Plasma Physics, and Fluid Dynamics
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Oscillation death in coupled oscillators
Wei ZOU (邹为)1,2, Xin-gang WANG (王新刚)3,4,5, Qi ZHAO (赵琪)1,2, Meng ZHAN (占萌)1 ( * )
1 Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
2 Graduate School of the Chinese Academy of Sciences, Beijing 100049, China
3 Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027, China
4 Temasek Laboratories, National University of Singapore, Singapore 117508, Singapore
5 Beijing-Hong Kong-Singapore Joint Centre for Nonlinear & Complex Systems (Singapore), National University of Singapore, 119260, Singapore
E-mail: zhanmeng@wipm.ac.cn
We study dynamical behaviors in coupled nonlinear oscillators and find that under certain conditions, a whole coupled oscillator system can cease oscillation and transfer to a globally nonuniform stationary state [i.e., the so-called oscillation death (OD) state], and this phenomenon can be generally observed. This OD state depends on coupling strengths and is clearly different from previously studied amplitude death (AD) state, which refers to the phenomenon where the whole system is trapped into homogeneously steady state of a fixed point, which already exists but is unstable in the absence of coupling. For larger systems, very rich pattern structures of global death states are observed. These Turing-like patterns may share some essential features with the classical Turing pattern.
pp 97―110
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Classification of three-dimensional quadratic diffeomorphisms with constant Jacobian
Zeraoulia ELHADJ, J. C. SPROTT (* )
1 Department of Mathematics, University of T′ebessa, 12002, Algeria
2 Department of Physics, University of Wisconsin, Madison,
WI 53706, USA
The 3-D quadratic diffeomorphism is defined as a map with a constant Jacobian. A few such examples are well known. In this paper, all possible forms of the 3-D quadratic diffeomorphisms are determined. Some numerical results are also given and discussed.
pp 111―121
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Soft Matter, Biological Physics, and Interdisciplinary Physics
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Entropy production in a cell and reversal of entropy flow as an anticancer therapy
Liao-fu LUO (罗辽复)
Laboratory of Theoretical Biophysics, Faculty of Science and Technology, Inner Mongolia University, Hohhot 010021, China
The entropy production rate of cancer cells is always higher than healthy cells in the case where no external field is applied. Different entropy production between two kinds of cells determines the direction of entropy flow among cells. The entropy flow is the carrier of information flow. The entropy flow from cancerous cells to healthy cells takes along the harmful information of cancerous cells, propagating its toxic action to healthy tissues….
pp 122―136
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Nonlinear property of slightly compressible media permeated with air-filled bubbles
Bo QIN (秦波)
College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
Based on the nonlinear oscillation of an airfilled bubble in weakly compressible media at prestressed state, the effective medium method is used to study the nonlinear property of the slightly compressible media permeated with air bubbles.
pp 137―142
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