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Bound Polaron in a Quantum Well Under an Electric Field 被引量:4
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作者 陈伟丽 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第5期787-791,共5页
We conduct a theoretical study on the properties of a bound polaron in a quantum well under an electric field using linear combination operator and unitary transformation methods, which are valid in the whole range of... We conduct a theoretical study on the properties of a bound polaron in a quantum well under an electric field using linear combination operator and unitary transformation methods, which are valid in the whole range of electron-LO phonon coupling. The changing relations between the ground-state energy of the bound polaron in the quantum well and the Coulomb bound potential, the electric field strength, and the well width are derived. The numerical results show that the ground-state energy increases with the increase of the electric field strength and the Coulomb bound potential and decreases as the well width increases. 展开更多
关键词 quantum well bound polaron ground-state energy linear combination operator electric field
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Influence of the Electric Field on the Properties of the Bound Magnetopolaron in GaAs Semiconductor Quantum Wells 被引量:3
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作者 单淑萍 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期438-441,共4页
The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformati... The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformation method. The relationships between the polaron's ground state energy and the Coulomb bound potential, electric field, magnetic field, and well-width are derived and discussed. Our numerical results show that the absolute value of the polaron's ground state energy increases as the electric field and the Coulomb bound potential increase, and decreases as the well-width and the magnetic field strength increase. When the well-width is small,the quantum size effect is significant. 展开更多
关键词 quantum well bound magnetopolaron linear combination operator ground state energy
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Investigation of Gate Defects in Ultrathin MOS Structures Using DTRS Technique
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作者 霍宗亮 杨国勇 +2 位作者 许铭真 谭长华 段小蓉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第11期1146-1153,共8页
s:A detailed description of relaxation spectroscopy technique under direct tunneling stress is given.A double peak phenomena by applied relaxation spectroscopy on ultra thin (<3nm) gate oxide is found.It suggests ... s:A detailed description of relaxation spectroscopy technique under direct tunneling stress is given.A double peak phenomena by applied relaxation spectroscopy on ultra thin (<3nm) gate oxide is found.It suggests that two kinds of traps exist in the degradation of gate oxide.It is also observed that both the trap density and the generation/capture cross section of oxide trap and interface trap are smaller in ultra thin gate oxide (<3nm) under DT stress than those in the thicker oxide (>4nm) under FN stress,and the centroid of oxide trap is closer to anode interface than in the center of oxide. 展开更多
关键词 TUNNELING metal oxide semiconductor device proportional difference operator
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INFLUENCE OF VIRTUAL PHOTON FIELD ON COLLAPSE AND REVIVAL PHENOMENON IN TWO PHOTON J C MODEL WITHOUT RWA
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作者 杨雁南 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期86-92,共7页
The time evolution of system in two photon Jaynes Cummings (J C) model without rotating waves approximation (RWA) is obtained by using the theory of ordinary differential equations. Based on the evolution, the mean ... The time evolution of system in two photon Jaynes Cummings (J C) model without rotating waves approximation (RWA) is obtained by using the theory of ordinary differential equations. Based on the evolution, the mean value of the atom inversion operator 〈 S 3(t)〉 is gi ven. The influence of the “counter rotating term” on the collapse and revival phenomenon is discussed from the comparison between the cases with RWA and without RWA. It shows that the influence of the virtual photon field makes the quantum fluctuations appear on the collapse and revival phenomenon. 展开更多
关键词 PHOTONS quantum noise J C model rotating waves approximation collapse and revival phenomenon atom inversion operator
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Inverse kinematic deriving and actuator control of Delta robot using symbolic computation technology
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作者 冯李航 张为公 +2 位作者 林国余 龚宗洋 陈刚 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期51-56,共6页
In order to effectively derive the inverse kinematic solution of the Delta robot and realize actuator control a description of the linear graph principle for automatically generating kinematic equations in a mechanica... In order to effectively derive the inverse kinematic solution of the Delta robot and realize actuator control a description of the linear graph principle for automatically generating kinematic equations in a mechanical system as well as the symbolic computation implementation of this procedure is reviewed and projected into the Delta robot. Based on the established linear graph representation the explicit symbolic expression of constraint equations and inverse kinematic solutions are obtained successfully using a symbolic computation engine Maple so that actuator control and trajectory tracking can be directly realized.Two practical motions the circular path and Adept motion are simulated for the validation of symbolic solutions respectively.Results indicate that the simulation satisfies the requirement of the quick motion within an acceptable threshold. Thus the precision of kinematic response can be confirmed and the correctness of inverse solution is verified. 展开更多
关键词 delta robot SYMBOLIC COMPUTATION inverse kinematic problems linear graph theory
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An enhanced iterative joint channel estimation and symbol detection algorithm for OFDM systems 被引量:1
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作者 韩冰 高西奇 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期103-107,共5页
For orthogonal frequency division multiplexing (OFDM) wireless communication, the system throughput and data rate are usually limited by pilots, especially in a high mobility environment. In this paper, an enhanced it... For orthogonal frequency division multiplexing (OFDM) wireless communication, the system throughput and data rate are usually limited by pilots, especially in a high mobility environment. In this paper, an enhanced iterative joint channel estimation and symbol detection algorithm is proposed to enhance the system throughput and data rate. With lower pilot power, the proposed scheme increases system throughput firstly, and then the channel estimation and symbol detection proceed iteratively within one OFDM symbol to improve the BER performance. In the proposed algorithm, the original channel estimate of each OFDM symbol is based on the channel estimate of the previous OFDM symbol, thus the variation of the mobile channel is traced efficiently, so the number of pilots in the time domain can be reduced greatly. Besides reducing the system overhead, the proposed algorithm is also shown by simulation to give much better BER performance than the conventional iterative algorithm does. 展开更多
关键词 OFDM channel estimation ITERATION multipath fading channel
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Improvement of Fuzzy Inference Mechanism in FuzzyJ Toolkit
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作者 吴沁奕 陈英 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期414-417,共4页
By applying the aggregation operator γ-operator and introducing a new method for global data contribution, the problems of information loss and the decrease of running efficiency in FuzzyJ Toolkit, an expert system s... By applying the aggregation operator γ-operator and introducing a new method for global data contribution, the problems of information loss and the decrease of running efficiency in FuzzyJ Toolkit, an expert system shell, can be effectively solved. The example shows that the approach can overcome imprecision of max-operator and min-operator used during the process of fuzzy reasoning. Therefore, the information accuracy and the system performance can be effectively improved, which promotes the usability of FuzzyJ Toolkit. 展开更多
关键词 FuzzyJ Toolkit γ-operator DEFUZZIFICATION global data contribution
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A note on the Marcinkiewicz integral operators on F_p^(α,q) 被引量:3
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作者 ZHANG Chun-jie QIAN Rui-rui 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第12期2037-2040,共4页
In this paper, we shall prove that the Marcinkiewicz integral operator #n, when its kernel Ω satisfies the L^1-Dini condition, is bounded on the Triehel-Lizorkin spaces. It is well known that the Triehel-Lizorkin spa... In this paper, we shall prove that the Marcinkiewicz integral operator #n, when its kernel Ω satisfies the L^1-Dini condition, is bounded on the Triehel-Lizorkin spaces. It is well known that the Triehel-Lizorkin spaces are generalizations of many familiar spaces such as the Lehesgue spaces and the Soholev spaces. Therefore, our result extends many known theorems on the Marcinkiewicz integral operator. Our method is to regard the Marcinkiewicz integral operator as a vector valued singular integral. We also use another characterization of the Triehel-Lizorkin space which makes our approach more clear. 展开更多
关键词 Marcinkiewicz integral Triebel-Lizorkin spaces Fourier transtforms
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New Bosonic Operator Ordering Identities Gained by the Entangled State Representation and Two-Variable Hermite Polynomials 被引量:3
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作者 FANHong-Yi FANYue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期297-300,共4页
Based on the technique of integration within an ordered product of operators, we derive new bosonic operators, ordering identities by using entangled state representation and the properties of two-variable Hermite pol... Based on the technique of integration within an ordered product of operators, we derive new bosonic operators, ordering identities by using entangled state representation and the properties of two-variable Hermite polynomials , and vice versa. In doing so, some concise normally (antinormally) ordering operator identities, such as : are obtained. 展开更多
关键词 operator ordering entangled state two-variable Hermite polynomials
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Relativistic Spin Operators 被引量:2
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作者 ZHANGPeng-Fei RUANTu-Nan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第3期293-300,共8页
A systematic theory on the appropriate spin operators for the relativistic states is developed. For a massive relativistic particle with arbitrary nonzero spin, the spin operator should be replaced with the relativist... A systematic theory on the appropriate spin operators for the relativistic states is developed. For a massive relativistic particle with arbitrary nonzero spin, the spin operator should be replaced with the relativistic one, which is called in this paper as moving spin. Further the concept of moving spin is discussed in the quantum field theory. A new operator, field quanta spin is defined and in terms of the generators of Poincaré group the moving spin of field system is constructed. It is shown that, in virtue of the two operators, problems in quantum field concerned spin can be neatly settled. 展开更多
关键词 canonical states moving spin field quanta spin
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Iterative Solution for Systems of Nonlinear Two Binary Operator Equations 被引量:2
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作者 ZHANGZhi-hong LIWen-feng 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第3期262-266,共5页
Using the cone and partial ordering theory and mixed monotone operator theory, the existence and uniqueness of solutions for some classes of systems of nonlinear two binary operator equations in a Banach space with a ... Using the cone and partial ordering theory and mixed monotone operator theory, the existence and uniqueness of solutions for some classes of systems of nonlinear two binary operator equations in a Banach space with a partial ordering are discussed. And the error estimates that the iterative sequences converge to solutions are also given. Some relevant results of solvability of two binary operator equations and systems of operator equations are improved and generalized. 展开更多
关键词 Banach spaces two binary operators systems of operator equations iterative solution
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Thermal Wigner Operator in Coherent Thermal State Representation and Its Application 被引量:3
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作者 FANHong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期289-292,共4页
In the coherent thermal state representation we introduce thermal Wigner operator and find that it is'squeezed' under the thermal transformation. The thermal Wigner operator provides us with a new direct and n... In the coherent thermal state representation we introduce thermal Wigner operator and find that it is'squeezed' under the thermal transformation. The thermal Wigner operator provides us with a new direct and neatapproach for deriving Wigner functions of thermal states. 展开更多
关键词 coherent thermal state thermal Wigner operator
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On the Laplacian Spectral Radius of Trees 被引量:2
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作者 TAN Shang-wang 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第4期615-625,共11页
Some sharp upper bounds of Laplacian spectral radius of trees in terms of order,diameter,pendant vertex number,covering number,edge covering number or total independence number are given.And the ninth to thirteenth la... Some sharp upper bounds of Laplacian spectral radius of trees in terms of order,diameter,pendant vertex number,covering number,edge covering number or total independence number are given.And the ninth to thirteenth largest values of Laplacian spectral radius over the class of trees on a given order are also given. 展开更多
关键词 Laplacian spectral radius TREE DIAMETER
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Constraints and Soliton Solutions for KdV Hierarchy and AKNS Hierarchy 被引量:2
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作者 李年华 李玉奇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期605-610,共6页
It is well-known that the finite-gap solutions of the KdV equation can be generated by its recursion operator. We generalize the result to a special form of Lax pair,from which a method to constrain the integrable sys... It is well-known that the finite-gap solutions of the KdV equation can be generated by its recursion operator. We generalize the result to a special form of Lax pair,from which a method to constrain the integrable system to a lower-dimensional or fewer variable integrable system is proposed.A direct result is that the n-soliton solutions of the KdV hierarchy can be completely depicted by a series of ordinary differential equations(ODEs),which may be gotten by a simple but unfamiliar Lax pair.Furthermore the AKNS hierarchy is constrained to a series of univariate integrable hierarchies.The key is a special form of Lax pair for the AKNS hierarchy.It is proved that under the constraints all equations of the AKNS hierarchy are linearizable. 展开更多
关键词 KdV hierarchy AKNS hierarchy soliton constraint
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Fractional Radon Transform and Transform of Wigner Operator 被引量:1
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作者 FANHong-Yi CHENJun-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第2期147-150,共4页
Based on the Radon transform and fractional Fourier transform we introduce the fractional Radon trans-formation (FRT). We identify the transform kernel for FRT. The FRT of Wigner operator is derived, which naturallyre... Based on the Radon transform and fractional Fourier transform we introduce the fractional Radon trans-formation (FRT). We identify the transform kernel for FRT. The FRT of Wigner operator is derived, which naturallyreduces to the projector of eigenvector of the rotated quadrature in the usual Radon transform case. 展开更多
关键词 fractional Radon transformation Wigner operator IWOP techneque
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Application of Eigenkets of Bosonic Creation Operator in Deriving Some New Formulas of Associated Laguerre Polynomials 被引量:1
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作者 FAN Hong-Yi WANG Tong-Tong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期315-320,共6页
Using the resolution of unity composed of bosonic creation operator's eigenkets and annihilation operator's un-normalized eigenket, which is a new quantum mechanical representation in contour integration form, we de... Using the resolution of unity composed of bosonic creation operator's eigenkets and annihilation operator's un-normalized eigenket, which is a new quantum mechanical representation in contour integration form, we derive new contour integration expression of associated Laguerre polynomials L^ρm (|z|^2) and its generalized generating function formula. A series of recursive relations regarding to L^ρm (|z|^2) are also deduced in the context of the Fock representation by algebraic method. 展开更多
关键词 bosonic creation operator Laguerre polynomials contour integration
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Probabilistic Controlled Teleportation of an Arbitrary Three-Qubit State 被引量:1
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作者 ZHA Xin-Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期637-639,共3页
Recently Jiang et al.[Chin.Phys.Lett.24 (2007) 1144] gave a scheme for probabilistic controlled tele-portation of a triplet W state from the sender Alice to the distant receiver Bob.The m controlled qubits are sharedb... Recently Jiang et al.[Chin.Phys.Lett.24 (2007) 1144] gave a scheme for probabilistic controlled tele-portation of a triplet W state from the sender Alice to the distant receiver Bob.The m controlled qubits are sharedby m(s_1,s_2,...,s_m) spatially-separated supervisors.Based on transformation operator,we can extend to teleporting anarbitrary three-qubit state.The relation between the transformation operators and the Bob's unitary transformation isalso obtained. 展开更多
关键词 controlled teleportation three-qubit state transformation operator
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Influence of Decoherence on Interference Between Two Bose-Einstein Condensates 被引量:1
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作者 ZENGAi-Hua KUANGLe-Man 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期41-44,共4页
The influence of decoherence on interference between two trapped Bose-Einstein condensates with arbitraryinitial states is studied. Analytic expressions of the intensity and visibility of the interference pattern are ... The influence of decoherence on interference between two trapped Bose-Einstein condensates with arbitraryinitial states is studied. Analytic expressions of the intensity and visibility of the interference pattern are found. It isshown that the decoherence weakens the interference intensity and decreases the visibility of the interference pattern. 展开更多
关键词 Bose-Einstein condensate DECOHERENCE INTERFERENCE
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An Approach to Unsupervised Character Classification Based on Similarity Measure in Fuzzy Model
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作者 卢达 钱忆平 +1 位作者 谢铭培 浦炜 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期370-376,共7页
This paper presents a fuzzy logic approach to efficiently perform unsupervised character classification for improvement in robustness, correctness and speed of a character recognition system. The characters are first ... This paper presents a fuzzy logic approach to efficiently perform unsupervised character classification for improvement in robustness, correctness and speed of a character recognition system. The characters are first split into eight typographical categories. The classification scheme uses pattern matching to classify the characters in each category into a set of fuzzy prototypes based on a nonlinear weighted similarity function. The fuzzy unsupervised character classification, which is natural in the repre... 展开更多
关键词 fuzzy model weighted fuzzy similarity measure unsupervised character classification matching algorithm classification hierarchy
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Multiverse and the Time State 被引量:2
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作者 Khaled (Moh'd Khalaf) Suleiman Alnobani 《Journal of Energy and Power Engineering》 2017年第3期160-163,共4页
This article is not inspired by any religion or quantum many-worlds interpretation. The mathematics of multiverse is presented here. The mass operator was introduced earlier by Alnobani. This operator is used here to ... This article is not inspired by any religion or quantum many-worlds interpretation. The mathematics of multiverse is presented here. The mass operator was introduced earlier by Alnobani. This operator is used here to deduce the time state. It is found that time has four states and those four states are orthogonal. Time is the constitution of any verse. Time has direction. Every orthogonal direction of time belongs to a verse. Past and future belong to opposite directions of time and they are arbitrary. Other verses are there by their own and not a probabilities of any other verse and if any similarity it is only a coincidence. Among applications of this thesis is travelling through groups of galaxies, or more or less. 展开更多
关键词 TIME MASS multiverse.
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