O437 2000031752磁场中耦合量子线的三阶非线性光学吸收率=Third-order nonlinear optical absorptions in dou ble-layered quantum wires with a perpendicularmagnetic field[刊,英]/郭康贤,陈传誉（广州师范学院物理系.广东,广州（5...O437 2000031752磁场中耦合量子线的三阶非线性光学吸收率=Third-order nonlinear optical absorptions in dou ble-layered quantum wires with a perpendicularmagnetic field[刊,英]/郭康贤,陈传誉（广州师范学院物理系.广东,广州（510400））//光子学报.—1999,28（2）.—97-100研究了磁场中耦合量子线的三阶非线性光学吸收率,并且利用密度矩阵算符理论导出了三阶非线性光学吸收率的解析表达式。最后,以GaAs/Al<sub>x</sub>Ga<sub>1-x</sub>As耦合量子线为例作了数值计算。展开更多
Based on the dielectric continuum model and Loudon＇s uniaxial crystal model,quasi-confined （QC） optical phonon modes and electron-QC phonon coupling functions in quasi-one-dimensional （QID） wurtzite quantum well ...Based on the dielectric continuum model and Loudon＇s uniaxial crystal model,quasi-confined （QC） optical phonon modes and electron-QC phonon coupling functions in quasi-one-dimensional （QID） wurtzite quantum well wires （QWWs） are deduced and analyzed. Numerical calculations on an AIN/GaN/AIN wurtzite QWW are performed. The results reveal that the dispersions of the QC modes are quite obvious only when the free wavenumber kz in the z-direction and the azimuthal quantum number m are small. The reduced behavior of the QC modes in wurtzite quantum systems is clearly observed. Through the discussion of the electron-QC mode coupling functions,it is found that the lower-frequency QC modes in the high-frequency region play a more important role in the electron-QC phonon interactions. Moreover,our computations also prove that kz and m have a similar influence on the electron-QC phonon coupling properties.展开更多
We investigate theoretically the spin current in a quantum wire with weak Dresselhaus spin-orbit coupling connected to two normal conductors. Both the quantum wire and conductors are described by a hard-wall confining...We investigate theoretically the spin current in a quantum wire with weak Dresselhaus spin-orbit coupling connected to two normal conductors. Both the quantum wire and conductors are described by a hard-wall confining potential. Using the electron wave-functions in the quantum wire and a new definition of spin current, we have calculated the elements of linear spin current density j^Ts,xi and j^Ts,yi（i=x, y, z）. We find that the elements j^Ts,xx and j^Ts,yy have a antisymmetrical relation and the element j^Ts,yz has the same amount levelas j^Ts,xx and j^Ts,yy. We also find a net linear spin current density, which has peaks at the center of quantum wire. The net linear spin current can induce a linear electric field, which may imply a way of spin current detection.展开更多
When the nonlinearity of nanomechanical resonator is not negligible, the quantum decoherenee of charge qubit is studied analytically. Using nonlinear Jaynes-Cummings model, one explores the possibility of being quantu...When the nonlinearity of nanomechanical resonator is not negligible, the quantum decoherenee of charge qubit is studied analytically. Using nonlinear Jaynes-Cummings model, one explores the possibility of being quantum data bus for nonlinear nanomechanical resonator, the nonlinearity destroys the dynamical quantum information-storage and maintains the revival of quantum coherence of charge qubit. With the calculation of decoherence factor, we demon- strate the influence of the nonlinearity of nanomechanical resonator on engineered decoherence of charge qubit.展开更多
文摘O437 2000031752磁场中耦合量子线的三阶非线性光学吸收率=Third-order nonlinear optical absorptions in dou ble-layered quantum wires with a perpendicularmagnetic field[刊,英]/郭康贤,陈传誉（广州师范学院物理系.广东,广州（510400））//光子学报.—1999,28（2）.—97-100研究了磁场中耦合量子线的三阶非线性光学吸收率,并且利用密度矩阵算符理论导出了三阶非线性光学吸收率的解析表达式。最后,以GaAs/Al<sub>x</sub>Ga<sub>1-x</sub>As耦合量子线为例作了数值计算。
文摘Based on the dielectric continuum model and Loudon＇s uniaxial crystal model,quasi-confined （QC） optical phonon modes and electron-QC phonon coupling functions in quasi-one-dimensional （QID） wurtzite quantum well wires （QWWs） are deduced and analyzed. Numerical calculations on an AIN/GaN/AIN wurtzite QWW are performed. The results reveal that the dispersions of the QC modes are quite obvious only when the free wavenumber kz in the z-direction and the azimuthal quantum number m are small. The reduced behavior of the QC modes in wurtzite quantum systems is clearly observed. Through the discussion of the electron-QC mode coupling functions,it is found that the lower-frequency QC modes in the high-frequency region play a more important role in the electron-QC phonon interactions. Moreover,our computations also prove that kz and m have a similar influence on the electron-QC phonon coupling properties.
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No.20060542002the Hunan Provincial Natural Science Foundation of China under Grant No.06JJ2097the Hunan College of Science and Technology Research Foundation of China under Grant No.07XKYTB001
文摘We investigate theoretically the spin current in a quantum wire with weak Dresselhaus spin-orbit coupling connected to two normal conductors. Both the quantum wire and conductors are described by a hard-wall confining potential. Using the electron wave-functions in the quantum wire and a new definition of spin current, we have calculated the elements of linear spin current density j^Ts,xi and j^Ts,yi（i=x, y, z）. We find that the elements j^Ts,xx and j^Ts,yy have a antisymmetrical relation and the element j^Ts,yz has the same amount levelas j^Ts,xx and j^Ts,yy. We also find a net linear spin current density, which has peaks at the center of quantum wire. The net linear spin current can induce a linear electric field, which may imply a way of spin current detection.
文摘When the nonlinearity of nanomechanical resonator is not negligible, the quantum decoherenee of charge qubit is studied analytically. Using nonlinear Jaynes-Cummings model, one explores the possibility of being quantum data bus for nonlinear nanomechanical resonator, the nonlinearity destroys the dynamical quantum information-storage and maintains the revival of quantum coherence of charge qubit. With the calculation of decoherence factor, we demon- strate the influence of the nonlinearity of nanomechanical resonator on engineered decoherence of charge qubit.
