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Preparation of Multi-cavity Entangled States

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Chinese Journal of Lasers 1998年第6期B7卷 55-57页

作者： ZHENG Shibiao (department of electronic Science and Applied physics, Fuzhou university, Fuzhou 350002, China) Fuzhou Univ Fuzhou China

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关键词： entangled state ladder type multi level atom resonant interaction

Feature combination for classifying single-trial ECoG during motor imagery of different sessions

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Progress in Natural Science:Materials International 2007年第7期17卷 851-858页

作者： Wei Qingguo~(1,2) Meng Fei~1 Wang Yijun~1 Gao Xiaorong~1 Gao Shangkai~(1**) (1.department of Biomedical engineering,School of Medicine,Tsinghua university,Beijing 100084.China 2.department of {4. engineering,School of Information,Nanchang university,Nanchang 330029,China) [a]department of Biomedical engineering School of Medicine TsinghuaUniversity Beijing China [b]department of electronic engineering School of Information Nanchang University Nanchang China

The input signals of brain-computer interfaces(BCIs)may be either scalp electroencephalogram(EEG)or electrocor- ticogram(ECoG)recorded from subdural *** make BCIs practical,the classifiers for discriminating different brain states must have the ability of session-to-session *** paper proposes an algorithm for classifying single-trial ECoG during motor imagery of different *** features,derived from two physiological phenomena,movement-related potentials(MRP)and event-related desynchronization(ERD),and extracted by common spatial subspace decomposition(CSSD)and waveform mean,are combined to per- form classification *** specific signal processing methods utilized are described in *** algorithm was successfully applied to Data SetⅠof BCI CompetitionⅢ,and achieved a classification accuracy of 91% on test set.

关键词： brain-computer interface(BCI) electrocorticogram(ECoG) session-to-session transfer feature combination movement-related potentials(MRP) event-related desynchronization(ERD)

Influence of modulation ratio on structure and properties of nanoscale ZrB_2/ZrAlN multilayered coatings

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Science China(Technological Sciences) 2010年第3期53卷 772-775页

作者： LI DeJun 1,KANG YuanBin 1,DONG Lei 1,DENG XiangYun 1,LIU Hao 2 &SUN XueLiang 2 1College of physics and electronic Information Science,Tianjin Normal university,Tianjin 300387,China 2 department of Mechanical&Materials {4.,university of Western Ontario,London ON,Canada 1. College of physics and electronic Information Science Tianjin Normal University Tianjin 300387 China2. Department of Mechanical & Materials Engineering University of Western Ontario London ON Canada

ZrB2/ZrAlN multilayered coatings with various modulation ratios(t ZrB2:t ZrAlN)and constant modulation periods were prepared by magnetron sputtering system at room ***,XRD,surface profiler and nano-indenter were employed to investigate the influences of tZ rB 2:tZrAlNon the microstructure and mechanical properties of the *** interfaces and nanoscale multilayered modulation were confirmed by *** multilayer with modulation period of 4. nm and ratio of 3:1 displayed the highest hardness(36.4.GPa)and critical fracture load(76.4.7 mN)with lower *** polycrystalline structure and multilayered modulate structure were directly responsible for the enhanced mechanical properties.

关键词： ZrB2/ZrAlN multilayered coating magnetron sputtering modulation ratio nanoscale

Internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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Science China Chemistry 2005年第5期48卷 395-401页

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.

Synthesis of some three-qubit gates and their implementation in a three spins system coupled with Ising interaction

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Science China(physics,Mechanics & Astronomy) 2010年第4期53卷 664-671页

作者： WEI HaiRui, DI YaoMin & WANG Yan School of physics & electronic engineering, Xuzhou Normal university, Xuzhou 221116, China 1. School of physics & electronic engineering Xuzhou Normal University Xuzhou 221116 China

The synthesis of the Toffoli gate, Fredkin gate, three-qubit Inversion-on-equality gate and D(α) gate, as well as their implementation in a three spins system coupled with Ising interaction are investigated. The sequences of the control pulse and the drift process to implement these gates are given. It is revealed that the implementation of some three-qubit gates in a circular spin chain is much better than in a linear spin chain, and every two measurements of the quantum computation complexity are not always consistent. It is significant to directly study the implementation of the multi-qubit gates and even more complicated components of quantum information processing without resorting to their synthesis.

关键词： three-qubit gate three spins system Ising interaction the sequences of control pulses and drift processes

Output Rate of Atomic Four-Wave Mixing in Two-Component Bose-Einstein Condensate

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Communications in Theoretical physics 2004年第5期41卷 695-698页

作者： LI Jia-Hua~1 LI Wei-Bing~1 PENG Ju-Cun~2 1 department of physics,Huazhong university of Science and Technology,Wuhan 4.0074.China2 department of physics,Xiaogan Normal university,Xiaogan 4.2100,China department of physics Xiaogan Normal University Xiaogan 432100 China

In this letter,following the proposal of Heurich et al.[***.A63(2001)033605],we analyze anddiscuss output rate of atomic four-wave mixing in the two-component Bose-Einstein condensate under the condition ofthe steady *** results show that the magnitude of the signal beam increases with the increase of the intensityof the probe beam,up to a saturated value,then it decreases as the probe beam *** influence of theinteraction range on the signal beam is also *** particular,it is worth while pointing out that in contrast tothe previous solutions,our obtained analytical solutions are of very simple and explicit forms,which open the door forfurther investigating the related physical mechanisms.

关键词： atomic four-wave mixing steady state Bose-Einstein condensate

The size effect on transport properties of colossal magnetoresistance materials La_(0.67)Ca_(0.33)MnO_3

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Science China(physics,Mechanics & Astronomy) 2008年第3期51卷 251-257页

作者： LI PeiGang1,2,LEI Ming1,2,GUO YanFeng2,GUO Xi2,CHEN LeiMing2, TANG WeiHua1,2,SONG PengYun3 & CHEN JinPing3 1 department of physics,Center for Optoelectronics Materials and Devices,Zhejiang Sci-Tech university,Hangzhou 310018,China 2 National Laboratory for Condensed Matter physics,Institute of physics,Chinese Academy of Sciences,Beijing 100080,China 3 department of physics,Peking university,Beijing 100875,China 1. department of physics Center for Optoelectronics Materials and Devices Zhejiang Sci-Tech University Hangzhou 310018 China 2. National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 3. department of physics Peking University Beijing 100875 China

High quality La0.67Ca0.33MnO3 (LCMO) film was deposited via a novel pulsed electron deposition technique on SrTiO3(100) single crystal substrate. The micro-bridge with different widths was fabricated by using electron beam lithography (EBL) technique and their transport properties were studied. For the micro-bridges with width of 2 and 1.5 μm,the insulator-to-metal transition temperature (TP) keeps un-changed compared with the film. For the micro-bridges with width of 1 μm,the TP shifts towards the lower temperature by 50 K. When the width decreases down to 500 nm,the insulator-to-metal transition disappears. The magnetoresistance be-havior of these micro-bridges was studied,and the results show that the low field magnetoresistance (LFMR) decreases and the high field magnetoresistances (HFMR) keep almost unchanged as the width of micro-bridge is reduced.

关键词： colossal magnetoresistance pulsed electron deposition electron beam lithography electrical transport properties

Lattice dynamical simulation of methane hydrate

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Journal of Natural Gas Chemistry 2010年第1期19卷 43-46页

作者： Lin Wang, Shunle Dong physics department, College of Information Science and engineering, Ocean university of China, Qingdao 266100, Shandong, China [a] physics department College of Information Science and Engineering Ocean University of China Qingdao 266100 Shandong China

INS （Inelastic Neutron Scattering） spectrum of methane hydrate was measured on MARI （a direct-geometry chopper spectrometer） at Ruther-ford Appleton Laboratory, UK. Compared with ice Ih, it is found that the whole spectrum of methane hydrate moves toward high-energy by about 1.5 meV. Using lattice dynamical （LD） technique, computer simulations of methane hydrate were carried out. In the simulations, four potential models （BE TIP3P, TIP4., MCY） were employed to calculate the phonon density of states （PDOS）. Comparing the calculated PDOS spectrum with the experimental spectrum, it is found that BF, TIP4., and TIP3P potential lattices give out well-separated translational and librational bands while MCY potential lattice is unstable to do so and this model is not suitable to describe hydrate system.

关键词： methane hydrate inelastic neutron scattering lattice dynamical simulation

Formation of bulk ferromagnetic nanostructured Fe_(4.)Ni_(4.)P_(14.B_6 alloys by metastable liquid spinodal decomposition

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Science China(Technological Sciences) 2009年第7期52卷 1919-1922页

作者： LI Qiang1,2 1 School of physics Science and Technology, Xinjiang university, Urumqi 83004., China 2 department of physics, The Chinese university of HongKong, Shatin N.T., HongKong, China School of physics Science and Technology Xinjiang University Urumqi 830046 China department of physics The Chinese University of HongKong Shatin N.T. HongKong China

Nanostructured Fe4.Ni4.P14.6 alloy ingots of 3―5 mm in diameter could be synthesized by a metastable liquid state spinodal decomposition method. For undercooling T> 260 K, the microstructure of the undercooled specimen had exhibited liquid state spinodal decomposition in the undercooled liquid state. The microstructure could be described as two intertwining networks with small grains dispersed in them. For undercooling T>290 K, the overall microstructure of the specimen changed into a granular morphology. The average grain sizes of the small and large grains are 30 nm and 80 nm, respectively. These prepared samples are soft magnets with saturation magnetization Bs 0.74. T.

关键词： nanomaterials magnetic materials solidification bulk nanostructured alloy Fe4.Ni4.P14.6 metastable liquid spinodal decomposition