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Bell States and Two-Qubit Logic Gate with Superconducting Charge Qubits Coupling to a Nanomechanical Resonator

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Communications in Theoretical Physics 2007年第12期48卷 999-1002页

作者： LIAO Jie-Qiao~1 and WANG Xin-Wen~(2,3.~1 department of Physics,Hunan Normal University,Changsha 410081,China~2 department of Physics,Beijing Normal University,Beijing 100875,China~3.department of {3. engineering and Physics,Hunan University of Science and engineering,Yongzhou 425100,China department of Physics Hunan Normal University Changsha 410081 China department of Physics Beijing Normal University Beijing 100875 China department of electronic engineering and Physics Hunan University of Science and Engineering Yongzhou 425100 China

We propose a scheme for generating Bell states involving two SQUID-based charge qubits by coupling themto a nanomechanical *** also show that it is possible to implement a two-qubit logic gate between the twocharge qu... 详细信息

关键词： Bell states superconducting charge qubit two-qubit logic gate nanomechanical resonator

Measurement errors of ultrasonic velocity and attenuation due to nonparallelness of specimen faces

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Chinese Journal of Acoustics 2003年第2期22卷 113-120页

作者： WEI Tingcun(department of electrical engineering, Tohoku University {3.) department of electrical engineering Tohoku University Japan

The measurement errors due to nonparallelness of specimen faces in the ultrasonic velocity and attenuation coefficient measured by the pulse reflection method in VHF range have been investigated theoretically, and the theoretical expressions for estimating these measurement errors are given. It has also been shown that, the attenuation coefficient error is depending on both the nonparallelness angle of specimen faces and the ultrasonic frequency, but the velocity error is only depending on the former. Furthermore, for pure silica glass specimen it is estimated that, in VHF range in order to insure that the attenuation coefficient and velocity errors due to nonparallelness of specimen faces are less than 10% and 0.01%, respectively, the nonparallelness angle of specimen faces must be less than 10 s and 40 s correspondingly.

关键词： of on it as Measurement errors of ultrasonic velocity and attenuation due to nonparallelness of specimen faces that is

Effect of diffraction on the ultrasonic velocity measuredby the pulse interference method in VHF range

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Chinese Journal of Acoustics 2002年第1期21卷 30-35页

作者： WEI Tingcun(department of electrical engineering, Tohoku University {3.) department of electrical engineering Tohoku University Japan

The effect of diffraction on the ultrasonic velocity measured by the pulse interference method has been investigated in VHF range theoretically and experimentally. Two silicate glasses are taken as the specimens, their frequency dependences of longitudinal velocities are measured in the frequency range of 50-3.0 MHz, and the phase advances of ultrasonic signals caused by diffraction effect are calculated using A. O. Williams' theoretical expression. For the velocity error due to diffraction effect, the experimental results are in good agreement with the theoretical prediction. It has been shown that the velocity error due to diffraction effect is directly proportional to dθ21 (f)/df, whereθ21 (f) is the phase advances difference between the two partial reflection signals used in velocity measurement and f is the ultrasonic frequency.

关键词： Effect of diffraction on the ultrasonic velocity measuredby the pulse interference method in VHF range VHF

An optimal adaptive filtering algorithm with a polynomial prediction model

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Science China(Information Sciences) 2011年第1期54卷 153-162页

作者： TAN JiaJia & ZHANG JianQiu department of electronic engineering,Fudan University,Shanghai 20043.,China department of electronic engineering Fudan University Shanghai China

A new approach to the optimal adaptive filtering is proposed in this *** this approach,a polynomial prediction model is used to describe the time-variant/invariant impulse response coeffcients of an identified *** the polynomial prediction model is viewed as the state equations of the identified impulse response coeffcients and the relationships between the inputs and outputs of the system are regarded as the measurements of the states,our adaptive filtering can be achieved in the framework of the Kalman filter. It is understood that Kalman filter is optimal in the sense of the MAP(maximum a posteriori),ML(most likelihood)and MMSE(minimum mean square error)under the linear and Gaussian white noise *** a result,our algorithm is also optimal in the statistical senses as Kalman filter does,provided that the impulse response coeffcients can be modeled by a *** only do the analytical results of the algorithm but also the simulation results show that our algorithm outperforms the traditional known algorithms.

关键词： adaptive filters polynomial prediction model impulse response coeffcients process equation Kalman filter optimal

Compact High-performance Bulk Optical Isolator

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Chinese Journal of Lasers 1998年第2期B7卷 31-36页

作者： WANG Lindou(department of electronic engineering,Tianjin University,Tianjin 3.0072,China) Tianjin Univ Tianjin China

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ＣｏｍｐａｃｔＨｉｇｈ┐ｐｅｒｆｏｒｍａｎｃｅＢｕｌｋＯｐｔｉｃａｌＩｓｏｌａｔｏｒＷＡＮＧＬｉｎｄｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｏｎｉｃＥｎｇｉｎｅｅｒｉｎｇ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａｎｊｉｎ３０００７２，Ｃｈｉｎａ）...

关键词： isolaton fiber optic communication bulk isolator

Repetitive learning control of nonlinear systems over finite intervals

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Science China(Information Sciences) 2010年第1期53卷 115-128页

作者： SUN MingXuan1, WANG DanWei2 & CHEN PengNian3.1College of Information engineering, Zhejiang University of Technology, Hangzhou 3.0014, China 2School of electrical and electronic engineering, Nanyang Technological University, Singapore 63.794 3.4} of Mathematics, China Institute of Metrology, Hangzhou 3.0018, China College of Information engineering Zhejiang University of Technology Hangzhou China School of electrical and electronic engineering Nanyang Technological University Singapore Singapore department of Mathematics China Institute of Metrology Hangzhou China

Iterative learning control requires initial repositioning, while the time functions to be learned should be of periodicity in repetitive control. However, there are cases in practice where the time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with avoidance of initial repositioning. In this paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. The Freeman formula is modified and used for stabilization of the nominal nonlinear time-varying system undertaken. The global stability of the learning system and asymptotic convergence of the tracking error are established through analysis of both partially and fully saturated learning algorithms, respectively. The repetitive learning control method is theoretically shown to be effective in dealing with time-varying parametric uncertainties.

关键词： Initial condition problem convergence iterative learning control repetitive control repetitive learning control nonlinear systems

Resistless photochemical etching of a silicon wafer by UV laser with an H_2O_2 and HF aqueous solution

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Chinese Science Bulletin 2002年第2期47卷 164-167页

作者： YANG Jie, LIU Yanfa & M. Murahara State Key Laboratory of Ultrafast Spectroscopy of Zhongshan University, Guangzhou 510275, China department of electrical engineering of Tokai University, {3. State Key Lab. Ultrafast Spectrosc. Zhongshan University Guangzhou 510275 China

A new resistless etching method has been de-veloped for Silicon wafers. This new method uses an aqueous solution consisting of hydrogen peroxide (H2O2) and hydro-gen fluoride (HF) as the activating etchants. A 193.nm ArF excimer laser and a 266 nm fourth harmonic generation Nd:YAG laser were used as the photon sources. Results showed that pattern etching has been achieved without any photoresist film. In the case of the 193.nm laser, the optimal etching appeared at a 1.3.H2O2/HF ratio, where an etchdepth of 210 nm was achieved with a fluence of 29 mJ/cm2 and shot number of 10000. At the same conditions, the etch depth with H2O2 and HF solution was three times of that by using H2O and HF mixture. In the case of the 266 nm Nd : YAG laser, the optimal etching appeared at twice ratio of H2O2/HF, where the etch depth of 420 nm was achieved witha fluence of 12 mJ/cm2 and shot number of 3.000. Results showed that the etch effect of the 266 nm Nd : YAG laser was more desirable than that of the 193.nm ArF

关键词： UV laser resistless photochemical etching hydrogen peroxide (H2O2).

Performance Analysis of Two CFAR Detectors in Clutter Edge Situation

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Journal of Systems engineering and electronics 2001年第2期12卷 44-51页

作者： He You department of electronic engineering, Naval Aeronautical engineering Academy Yantai 264001, P. R. China Guan Jian department of electronic engineering, Tsinghua University, Beijing 100084, R R. China department of electronic engineering Naval Aeronautical Engineering Academy Yantai 264001 P. R. China department of electronic engineering Tsinghua University Beijing 100084 P. R. China

This paper studies the performance of the GOSGO and GOSSO CFAR detectors [1] in clutter edge situation. The authors derive the analytic expressions of the false alarm probabilities in that situation, analyze their performances against clutter edge, and compare them with the OS, CA, GO and SO detectors. The results show that GOSGO possesses better performance than GO for countering clutter, but the performance of GOSSO is very unideal.

关键词： Alarm systems Clutter (information theory) Gaussian noise (electronic) Signal to noise ratio White noise

A Comparative Study of Boron and Phosphorus Doping Effects in SiC: H Films Prepared by ECR-CVD

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Journal of Materials Science & Technology 1998年第1期14卷 65-71页

作者： S.F. Yoon (School of electrical and electronic engineering, Nanyang Technological University, Nanyang Avenue,Singapore 63.798, Rep. of Singapore) School of electrical and electronic engineering Nanyang Technological University Nanyang Avenue Singapore 639798 Singapore

Hydrogenated silicon carbide films (SiC:H) were deposited using the electron cyclotron resonance chemical vapour deposition (ECR-CVD) technique from a mixture of methane, silane and hydrogen, and using diborane and phosphine as doping gases. The effects of changes in the microwave power on the deposition rate and optical bandgap were investigated, and variations in the photoand dark-conductivities and activation energy were studied in conjunction with film analysis using the Raman scattering technique. In the case of boron-doped samples, the conductivity increased rapidly to a maximum, followed by rapid reduction at high microwave power. The ratio of the photo- to dark-conductivity (σph/σd) peaked at microwave power of ~600 W. Under conditions of high microwave power, Raman scattering analysis showed evidence of the formation and increase in the silicon microcrystalline and diamond-like phases in the films, the former of which could account for the rapid increase and the latter the subsequent decrease in the *** the case of phosphorusdoped SiC:H samples, it was found that increase in the microwave power has the effect of enhancing the formation of the silicon microcrystalline phase in the films which occurred in correspondence to a rapid increase in the conductivity and reduction in the activation energy The conductivity increase stabilised in samples deposited at microwave power exceeding 500 W probably as a result of dopant saturation. Results from Raman scattering measurements also showed that phosphorus doping had the effect of enhancing the formation of the silicon microcrystals in the film whereas the presence of boron had the effect of preserving the amorphous structure.

关键词： ECR A Comparative Study of Boron and Phosphorus Doping Effects in SiC H Films Prepared by ECR-CVD