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Probing New physics from CP Violation in Radiative B Decays

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Chinese physics Letters 1999年第5期16卷 339-341页

作者： wu Yue-liang institute of theoretical{2. Chinese Academy of SciencesBeijing 100080

When new CP-violating interactions are dominated by flavor changing neutral particle exchanges,which may occur in many extensions of the standard model,we examine a type-3 two-Higgs-doublet model and find that direct CP asymmetries can be as large as about 2.%.Time-dependent and time-integrated mixing-induced CP asymmetries up to 85 and 40%,respectively,are possible without conflict with other *** mainly requirs an enhanced chromo-magnetic dipole b→sg decay to be close to the present experimental bound.

关键词： neutral mixing decay

Generalized Thermal Instability Criterion of Black Hole Accretion Disks

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Chinese physics Letters 1998年第7期15卷 542-544页

作者： wu Xue-bing beijing Astronomical Observatory Chinese Academy of SciencesBeijing 100012 institute of theoretical{2. Chinese Academy of SciencesBeijing 100080

The conventional thermal instability criterion cannot be applied to the advection-dominated accretion disks around black holes where the radiative cooling is insufficient to balance the viscous *** surface density change associated with the temperature perturbations,which was usually neglected in deriving the conventional criterion,was recently shown to be much significant in the advection-dominated *** both advection and surface density change,a generalized thermal instability criterion is *** applying it to the optically thin and optically thick advection-dominated disks,it is found that the former one is thermally stable and the latter one is thermally unstable against short wavelength perturbations,which agrees well to those found recently by both analytic and quantitative stability analyses.

关键词： criterion perturbations Criterion

Clifford Algebras and Homogeneous Geometric Models

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Clifford Algebras and Homogeneous Geometric Models

Quantum tunneling of ultracold atoms in optical traps

CCAST“蛋白质结构分析中的一些问题”研讨会

作者： Hongbo Li Academy of Mathematics and System Sciences Chinese Academy of Sciences beijing 1.0080,{2. Email:hli@***

＜正＞ 1 IntroductionThis paper is based on a talk at the First Conference on Protein Structure in beijing, November 18-2., 2.02. and another talk at the Seminar held by Prof. Ke wu in the {2. of {2. physics of the Chinese Academy of Sciences. beijing, December 19, *** talks are on an "old" algebraic language - Clifford algebra, and its applications in geometric computing. Clifford algebra has a history of about 150 years. Its modern definition is as follows.

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Frontiers of physics 2014年第2期9卷 137-152页

作者： Jian-Hua wu Ran Qi An-Chun Ji wu-Ming Liu beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We review our theoretical advances in quantum tunneling of BoseEinstein condensates in optical traps and in microcavities. By employing a real physical system, the frequencies of the pseudo Goldstone modes in different phases between two optical traps are studied respectivdy, which are tile crucial feature of the non-Abelian Joseptmon effect. When the optical lattices are under gravity, we investigate the quantum tummling in the ＂Wannier-Stark localization＂ regime and ＂Lan（lau Zener tunneling＂ regime. We finally get the total decay rate and the rate is valid over the entire range of temperatures. At high temperatures, we show how the decay rate reduces to the appropriate results for the classical thermal activation. At hltermediate temperatures, the results of tile total decay rate are consistent with the thermally assisted tunneling. At low temperatures, we obtain the pure quantmn tunneling ultimately. And we study the alternating-current and direct-current （ac and de） photonic 3osephson effects in two weakly linked microcavities containing ultracold two-level atones, which allows for direct observation of the effects. This enables new investigations of the effect of maw-body physics in strongly coupled atom-cavity systems and provides a strategy for constructing novel interference devices of coherent photons. In addition, we propose the experimental protocols to observe these quantmn tunneling of Bose- Einstein condensates.

关键词： quantum tunneling Josephson effect Landau-Zener tunneling atom-cavity

Air Stability of Solid‑State Sulfide Batteries and Electrolytes

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Electrochemical Energy Reviews 2022年第3期5卷 213-258页

作者： Pushun Lu Dengxu wu Liquan Chen Hong Li Fan wu Tianmu Lake institute of Advanced Energy Storage Technologies Liyang 213300JiangsuChina Yangtze River Delta physics Research Center Liyang 213300JiangsuChina beijing Advanced Innovation Center for Materials Genome Engineering Key Laboratory for Renewable EnergyBeijing Key Laboratory for New Energy Materials and DevicesInstitute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

Sulfides have been widely acknowledged as one of the most promising solid electrolytes(SEs)for all-solid-state batteries(ASSBs)due to their superior ionic conductivity and favourable mechanical ***,the extremely poor air stability of sulfide SEs leads to destroyed structure/performance and release of toxic H_(2.S gas,which greatly limits mass-production/practical application of sulfide SEs and *** review is designed to serve as an all-inclusive handbook for studying this critical ***,the research history and milestone breakthroughs of this field are reviewed,and this is followed by an in-depth elaboration of the theoretical paradigms that have been developed thus far,including the random network theory of glasses,hard and soft acids and bases(HSAB)theory,thermodynamic analysis and kinetics of interfacial ***,the characterization of air stability is reviewed from the perspectives of H2. generation,morphology evolution,mass change,component/structure variations and electrochemical ***,effective strategies for improving the air stabilities of sulfide SEs are highlighted,including H_(2.S absorbents,elemental substitution,design of new materials,surface engineering and sulfide-polymer composite ***,future research directions are proposed for benign development of air stability for sulfide SEs and ASSBs.

关键词： Sulfide solid electrolytes Air stability Superionic conductors All-solid-state batteries

Numerical Investigation of the Slow Acoustic Wave Modes in a One-Dimensional Phononic Crystal Plate

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Chinese physics Letters 2013年第8期30卷 122-124页

作者： ZHANG Xu AN Zhi-wu State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190

The propagation of Lamb waves in a two-layered free standing plate composed of a one-dimensional photonic crystal thin layer coated on uniform substrates of different thicknesses is investigated numerically by the finite element *** concentrate on the theoretical demonstration of the existence of very slow group velocity at the nearly flat band in specially designed phononic crystal plates and show that the group velocity can be tuned from positive to negative gradually as the thickness of the substrate layer *** applications in new acoustic devices are described.

关键词： method crystal layered

Optimal control of quantum systems with SU(1,1)dynamical symmetry

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Control Theory and Technology 2015年第3期13卷 211-220页

作者： Wenbin DONG Rebing wu Jianwu wu Chunwen LI Tzyh-Jong TARN Department of Automation Tsinghua University Center for Quantum Information Science and Technology Tsinghua National Laboratory for Information Science and Technology(TNlist) beijing Aerospace Automatic Control institute Electrical and Systems Engineering Department Washington University in St.Louis

SU（1,1） dynamical symmetry is of fundamental importance in analyzing unbounded quantum systems in theoretical and applied physics. In this paper, we study the control of generalized coherent states associated with quantum systems with SU（1,1） dynamical symmetry. Based on a pseudo Riemannian metric on the SU（1,1） group, we obtain necessary conditions for minimizing the field fluence of controls that steer the system to the desired final state. Further analyses show that the candidate optimal control solutions can be classified into normal and abnormal extremals. The abnormal extremals can only be constant functions when the control Hamiltonian is non-parabolic, while the normal extremals can be expressed by Weierstrass elliptic functions according to the parabolicity of the control Hamiltonian. As a special case, the optimal control solution that maximally squeezes a generalized coherent state is a sinusoidal field, which is consistent with what is used in the laboratory.

关键词： Quantum control optimal control dynamical symmetry

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磁场下碳化物析出的热力学机制

原子与分子物理学报 2025年第4期42卷 127-136页

作者：廖已莹侯廷平杨雨豪郑一航于涛刘伍明吴开明武汉科技大学理学院冶金工业过程系统科学湖北省重点实验室省部共建耐火材料与冶金国家重点实验室江汉大学光电材料与技术学院光电化学材料与器件教育部重点实验室中国科学院物理研究所

钢中碳化物的形成主要由合金元素的种类以及含量的决定，碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M6C（M=Fe, Mo）作为研究对象，利用第一性原理计算η-Fe2...

钢中碳化物的形成主要由合金元素的种类以及含量的决定，碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M6C（M=Fe, Mo）作为研究对象，利用第一性原理计算η-Fe2.、Fe3C、Fe2.o4C、Fe3Mo3C-I、Fe3Mo3C-II和Fe4Mo2.等合金碳化物的磁矩，计算结果表明其中Fe4Mo2.的磁矩最大，达到了7.04μB.磁矩不仅由碳化物晶胞中Fe原子个数有关，还与Fe Wyckoff占位紧密相关.通过模拟计算碳化物的磁致磁热熔、磁熵、磁焓和磁自由能，从热力学角度对各碳化物进行分析，结果表明磁场会使碳化物的磁致磁热熔和磁熵增加；强磁场会降低M6C的磁自由能进而提高其稳定性.此工作为研究核聚变材料磁性能提供理论基础和技术参考.

关键词：磁场碳化物析出相热力学机制

Equation of Motion of a Mass Point in Gravitational Field and Classical Tests of Gauge Theory of Gravity

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Communications in theoretical physics 2007年第3期47卷 503-511页

作者： wu Ning ZHANG Da-Hua institute of High Energy physics P.O. Box 918-1 Beijing 100039 China

A systematic method is developed to studY the classical motion of a mass point in gravitational gauge field. First, by using Mathematica, a spherical symmetric solution of the field equation of gravitational gauge field is obtained, which is just the traditional Schwarzschild solution. Combining the principle of gauge covariance and Newton＇s second law of motion, the equation of motion of a mass point in gravitational field is deduced. Based on the spherical symmetric solution of the field equation and the equation of motion of a mass point in gravitational field, we can discuss classical tests of gauge theory of gravity, including the deflection of light by the sun, the precession of the perihelia of the orbits of the inner planets and the time delay of radar echoes passing the sun. It is found that the theoretical predictions of these classical tests given by gauge theory of gravity are completely the same as those given by general relativity.

关键词： classical tests of gauge theory of gravity gauge theory of gravity classical solution of field equation Newton's second law of motion