TN242 2003053408高斯型变反射率圆镜平凹腔本征模场的矩阵分析=Matrixanalysis of eigen mode-fields of the circular plano-concaveresonator with a Gaussian-reflectivity mirror[刊,中]/凌东雄(昆明理工大学激光应用研究所.云南,...TN242 2003053408高斯型变反射率圆镜平凹腔本征模场的矩阵分析=Matrixanalysis of eigen mode-fields of the circular plano-concaveresonator with a Gaussian-reflectivity mirror[刊,中]/凌东雄(昆明理工大学激光应用研究所.云南,昆明(650093)),伏云昌…//中国激光.-2003,30(1).-25-28利用柱坐标下的柯林斯公式,将圆镜平凹腔的衍射积分方程转化为矩阵方程,并对平面镜反射率呈高斯分布的圆镜平凹腔的模场分布进行了数值分析,结果证明平面镜反射率呈高斯分布的圆镜平凹腔具有良好的选模性能。图3参7(李瑞琴)TN242展开更多
Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the co...Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the conventional field-effect transistor （FET） method. The dielectric responses of SWNTs are strongly correlated with electronic transport of the corresponding FETs. The DC bias voltage in DFM plays a role analogous to the gate voltage in FET. A microscopic model based on the general continuity equation and numerical simulation is built to reveal the link between intrinsic properties such as carrier concentration and mobility and the macroscopic observable, i.e. dielectric responses, in DFM experiments. Local transport barriers in nanotubes, which influence the device transport behaviors, are also detected with nanometer scale resolution.展开更多
Two linear In this letter, we prove the following conclusions by introducing a function Fn（t）： （1） If a quantum system S with a time-dependent non-degenerate Hamiltonian H（t） is initially in the n-th eigenstate...Two linear In this letter, we prove the following conclusions by introducing a function Fn（t）： （1） If a quantum system S with a time-dependent non-degenerate Hamiltonian H（t） is initially in the n-th eigenstate of H（0）, then the state of the system at time t will remain in the n-th eigenstate of H（t） up to a multiplicative phase factor if and only if the values Fn（t） for all t are always on the circle centered at 1 with radius 1; （2） If a quantum system S with a time-dependent Hamiltonian H（t） is initially in the n-th eigenstate of H（0）, then the state of the system at time t will remain c-uniformly approximately in the n-th eigenstate of H（t） up to a multiplicative phase factor if and only if the values F,（t） for all t are always outside of the circle centered at 1 with radius 1-ε. Moreover, some quantitative sufficient conditions for the state of the system at time t to remain ε-uniformly approximately in the n-th eigenstate of H（t） up to a multiplicative phase factor are established. Lastly, our results are illustrated by a spin-half particle in a rotating magnetic field.展开更多
Under the influence of an applied magnetic field(MF), the eigenenergies and the eigenfunctions of the ground and the first excited states(GFES) are obtained by using a variational method of the Pekar type(VMPT) in a s...Under the influence of an applied magnetic field(MF), the eigenenergies and the eigenfunctions of the ground and the first excited states(GFES) are obtained by using a variational method of the Pekar type(VMPT) in a strong electron-LO-phonon coupling asymmetrical Gaussian potential quantum well(AGPQW). This AGPQW system may be employed as a two-level qubit. The numerical results have indicated(i) that when the electron situates in the superposition state of the GFES, we obtain the time evolution and the coordinate change of the electron probability density in the AGPQW,(ii) that due to the presence of the asymmetrical potential in the growth direction of the AGPQW, the probability density shows double-peak configuration, whereas there is only one peak if the confinement is a two dimensional symmetric one in the xy plane of the AGPQW,(iii) that the oscillatory period is a decreasing function of the cyclotron frequency of the MF, the height of the AGPQW and the polaron radius,(iv) and that as the range of the confinement potential(RCP) decreases the oscillatory period will decrease firstly and then increase and it will take a minimum when R =-0.234 nm.展开更多
We show that the（2＋1）-dimensional Dirac-Moshinsky oscillator coupled to an externa/ magnetic field can be treated algebraically with the SU（1,1） group theory and its group basis.We use the su（1,1） irreducible r...We show that the（2＋1）-dimensional Dirac-Moshinsky oscillator coupled to an externa/ magnetic field can be treated algebraically with the SU（1,1） group theory and its group basis.We use the su（1,1） irreducible representation theory to find the energy spectrum and the eigenfunctions.Also,with the su（1,1） group basis we construct the relativistic coherent states in a closed form for this problem.展开更多
The two-dimensional Dirac equation for a fermion moving under Kratzer potential in the presence of an external magnetic field is analytically being solved for the energy eigenvalues and eigenfunctions. Subsequently, w...The two-dimensional Dirac equation for a fermion moving under Kratzer potential in the presence of an external magnetic field is analytically being solved for the energy eigenvalues and eigenfunctions. Subsequently, we have obtained the Wigner function corresponding to the eigenfunctions.展开更多
文摘探究了含有多个椭球夹杂的双材料和半无限大空间的稳态传热解.双材料的界面由包含连续性条件的双材料空间格林函数考虑,通过调整参数,该函数可退化为半无限大空间或者无限大空间格林函数.利用Eshelby等效夹杂法(equivalent inclusion method,EIM),将椭球夹杂等效为基底材料和夹杂内连续分布的本征温度梯度场.基于含多项式密度的椭球积分,椭球夹杂的扰动作用由本征温度梯度场和双材料格林函数域积分精确描述.本征场由夹杂形心展开的泰勒级数,并通过各个夹杂形心建立的多项式等效热流方程求解,求解精度由有限元法(finite element method,FEM)验证,实现了无网格求解双材料和半无限大空间中多个椭球夹杂的稳态传热问题.
文摘TN242 2003053408高斯型变反射率圆镜平凹腔本征模场的矩阵分析=Matrixanalysis of eigen mode-fields of the circular plano-concaveresonator with a Gaussian-reflectivity mirror[刊,中]/凌东雄(昆明理工大学激光应用研究所.云南,昆明(650093)),伏云昌…//中国激光.-2003,30(1).-25-28利用柱坐标下的柯林斯公式,将圆镜平凹腔的衍射积分方程转化为矩阵方程,并对平面镜反射率呈高斯分布的圆镜平凹腔的模场分布进行了数值分析,结果证明平面镜反射率呈高斯分布的圆镜平凹腔具有良好的选模性能。图3参7(李瑞琴)TN242
文摘Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the conventional field-effect transistor （FET） method. The dielectric responses of SWNTs are strongly correlated with electronic transport of the corresponding FETs. The DC bias voltage in DFM plays a role analogous to the gate voltage in FET. A microscopic model based on the general continuity equation and numerical simulation is built to reveal the link between intrinsic properties such as carrier concentration and mobility and the macroscopic observable, i.e. dielectric responses, in DFM experiments. Local transport barriers in nanotubes, which influence the device transport behaviors, are also detected with nanometer scale resolution.
基金supported by the National Natural Science Foundation of China(Grant No. 11171197)the IFGP of Shaanxi Normal University(Grant No. 2011CXB004)the FRF for the Central Universities(Grant No. GK201002006)
文摘Two linear In this letter, we prove the following conclusions by introducing a function Fn（t）： （1） If a quantum system S with a time-dependent non-degenerate Hamiltonian H（t） is initially in the n-th eigenstate of H（0）, then the state of the system at time t will remain in the n-th eigenstate of H（t） up to a multiplicative phase factor if and only if the values Fn（t） for all t are always on the circle centered at 1 with radius 1; （2） If a quantum system S with a time-dependent Hamiltonian H（t） is initially in the n-th eigenstate of H（0）, then the state of the system at time t will remain c-uniformly approximately in the n-th eigenstate of H（t） up to a multiplicative phase factor if and only if the values F,（t） for all t are always outside of the circle centered at 1 with radius 1-ε. Moreover, some quantitative sufficient conditions for the state of the system at time t to remain ε-uniformly approximately in the n-th eigenstate of H（t） up to a multiplicative phase factor are established. Lastly, our results are illustrated by a spin-half particle in a rotating magnetic field.
基金Supported by the National Science Foundation of China under Grant No.11464034
文摘Under the influence of an applied magnetic field(MF), the eigenenergies and the eigenfunctions of the ground and the first excited states(GFES) are obtained by using a variational method of the Pekar type(VMPT) in a strong electron-LO-phonon coupling asymmetrical Gaussian potential quantum well(AGPQW). This AGPQW system may be employed as a two-level qubit. The numerical results have indicated(i) that when the electron situates in the superposition state of the GFES, we obtain the time evolution and the coordinate change of the electron probability density in the AGPQW,(ii) that due to the presence of the asymmetrical potential in the growth direction of the AGPQW, the probability density shows double-peak configuration, whereas there is only one peak if the confinement is a two dimensional symmetric one in the xy plane of the AGPQW,(iii) that the oscillatory period is a decreasing function of the cyclotron frequency of the MF, the height of the AGPQW and the polaron radius,(iv) and that as the range of the confinement potential(RCP) decreases the oscillatory period will decrease firstly and then increase and it will take a minimum when R =-0.234 nm.
基金Supported by SNI-Mexico,COFAA-IPN,EDI-IPN,EDD-IPN,SIP-IPN project number 20140598
文摘We show that the（2＋1）-dimensional Dirac-Moshinsky oscillator coupled to an externa/ magnetic field can be treated algebraically with the SU（1,1） group theory and its group basis.We use the su（1,1） irreducible representation theory to find the energy spectrum and the eigenfunctions.Also,with the su（1,1） group basis we construct the relativistic coherent states in a closed form for this problem.
文摘The two-dimensional Dirac equation for a fermion moving under Kratzer potential in the presence of an external magnetic field is analytically being solved for the energy eigenvalues and eigenfunctions. Subsequently, we have obtained the Wigner function corresponding to the eigenfunctions.
