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91.
Considering that the coupling among the heavy-hole exciton,light-hole exciton and the cavity photon can form bipolaritons in a quantum semiconductor microcavity,we calculate the group velocities of the cavity polaritons at different incident angles using the coupling model of three harmonic oscillators.The result indicates that the group velocities of the low and middle branches of the cavity polaritons have extrema,but the group velocities of the high branch increase with the increasing incident angle.  相似文献   
92.
The influence of N2 plasma annealing on the properties of fluorine doped silicon oxide (SiOF) films is investigated.The stability of the Dielectric constant of SiOF film is remarkably improved by the N2 plasma annealing.After enduring a moisture absorption test for six hours in a chamber with 60% humidity at 50℃,the dielectric constant variation of the annealed SiOF films is only 1.5%,while the variation for those SiOF films without annealing is 15.5%.Fourier transform infrared spectroscopic results show that the absorption peaks of Si-OH and H-OH of SiOF films are reduced after the N2 plasma annealing because the annealing can wipe off some unstable Si-F2 bonds in SiOF films.These Unstable Si-F2 bonds are suitable to react with water,resulting in the degradation of SiOF film properties.Therefore,the N2 plasma annealing meliorates the properties of SiOF films with low dielectric constant.  相似文献   
93.
The moist potential vorticity (MPV) equation is derived from complete atmospheric dynamic equations with both heat and mass forcings,with which the impermeability theorem of the “MPV substance” is proven.It is clarified that both heat and mass forcings induced by the intensive precipitation in torrential rain systems can lead to the MPV anomaly.The MPV substance anomaly is a dynamical tracer for tracking a torrential rain system.  相似文献   
94.
蔡浩  石兢 《中国物理快报》2002,19(7):908-911
The sine-Gordon equation is solved in a laboratory reference using the method of Darboux transformation.Using the Liouville theorem,explicit expressions of the single soliton solution and the breather solution are derived from the Darboux matrix in the case of a null spectral parameter.  相似文献   
95.
The on-line time differential perturbed angular correlation technique has been developed for the first time.The quadrupole interaction of ^19F in Cd was measured.  相似文献   
96.
The quasi-static magnetic fields created in the interaction of relativistic laser pulses with under-dense plasmas have been investigated by three-dimensional particle-in-cell simulation.The relativistic ponderomotive force can drive and intense electron current in the laser propagation direction,which is responsible for the generation of a helical magnetic field.The axial magnetic field results from a difference bean of wave-wave,which drives a solenoidal current.In particular,the physical significance of the kinetic model for the generation of the axial magnetic field is discussed.  相似文献   
97.
We study the energy levels of an electron (or hole) polaron in a parabolic quantum well structure,including the spatial dependence of the effective mass.We also consider the two-mode behaviour of longitudinal optical phonon modes of the ternary mixed crystals in the structure,in the calculation of the effect of the electron phonon interaction.We calculate the ground state,the first excited state and the transition energy of an electron (or hole) in the GaAs/AlxGa1-xAs parabolic quantum well structure.The numerical results show that the electron-phonon interaction obviously affects the energy levels of the electron (or hole),which are in agreement with experimental results.  相似文献   
98.
The magnetic properties and magnetoresistance effect of YMn6Sn6-x Crx(x=0-0.8) compounds have been experimentally studied by magnetic properties and resistivity measurements in the applied field range 0-5T.The compound (x=0.8) displays a ferromagnetic behaviour,while the compounds (x=0-0.4) display an antiferromagnetic behaviour in the whole ordering temperature range.The compounds(x=0.5,0.6) experienced a transition from an antiferromagnetic state to a ferromagnetic state with increasing temperature.The compound with x=0.8 is rapidly saturated in the lower magnetic field with saturation magnetization of 35.92emu/g.The compounds(x=0-0.6) display a field-induced metamagnetic transition,and the threshold fields decrease with increasing Cr content.The cell-volume V of compounds(x=0-0.8) increases,and the ordering temperature decreases with the increasing Cr content.A large magnetoresistance effect was observed for the compounds (x=0.4,0.5),and the maximum absolute value at 5K are 32% and 24% under 5T for x=0.4 and x=0.5,respectively.  相似文献   
99.
By using the normal-ordering technique in the coherent state representation,we discuss the dynamical evolution of the coherence of a Schrodinger cat state in a high Q cavity coupled to another resonator in the presence of external fields.During the progression of the coherence,we pay particular attention to the effect of the external fields,as well as to the initial phase of the Schrodinger cat state.  相似文献   
100.
We have experimentally realized the Fredkin gate with only three transition pulses in a solution of alanine.It appears that no experimental realization of the Fredkin gate with fewer pulses has been reported yet.In addition,the simple structure of our scheme makes it easy to implement in experiments.  相似文献   
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