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81.
We study the quantum fluctuations of the charge and current of two L-C dissipative mesoscopic circuit with the mutual inductance in the vacuum state.Our results show that the system state will evolve to a squeezed coherent state under the effect of external source.We find that the squeezing amplitude parameter is relative to the parameters of circuit and the mutual-inductance coefficient in the existence of dissipation.When the circuit has no dissipation or there is complete coupling between two meshes,the squeezing amplitude parameter only depends on the capacitance‘s ratio.  相似文献   
82.
The rotational band built on the i13/2 proton [660,1/2] Nilsson state in ^173Re is proven to be identical to that in ^171Ta.The close similarity of the two bands in ^171Ta and ^173Re suggests that the ^173Re nucleus with the odd proton based on the i13/2 [660,1/2] Nilsson state may be triaxially superdeformed.  相似文献   
83.
Distorted Wave Effects of the 1b3g Orbital in Ethylene   总被引:1,自引:0,他引:1       下载免费PDF全文
We study the unexpected distorted wave effects of the 1b3g orbital in ethylene using a high resolution binary (e,2e) electron momentum spectrometer,at an impact energy of 800eV plus the binding energy (8-22eV) with symmetric non-coplanar kinematics.The experimental monentum profile of the 1b3g orbital is obtained and compared with the data previously measured at an impact energy of 1200 eV plus the binding energy.Also,the experimental momentum profiles of the 1b3g orbital are compared with the theoretical momentum distributions calculated by using Hartree-Fock and density functional theory methods.The experimental momentum profiles of the 1b3g orbital of ethylene at different impact energies show that the cross section of the orbital below the momentum p-1 a.u.is higher for lower impact energies.  相似文献   
84.
We study Rayleigh-enhanced nondegenerate four-wave mixing (NFWM) with time-delayed,correlated fluctuating fields.The importance of the field correlation is revealed in the Rayleigh-enhanced NFWM spectrum when the time delay is varied.The Rayleigh-enhanced NFWM is employed to study the ultrafast processes in the frequency domain.A relaxation time as short as 220 fs was deduced in the Rayleigh-enhanced NFWM experiments in carbon disulphide.  相似文献   
85.
A new harge absolute photonic bandgap at high normalized frequencies can be obtained in a two-dimensional hexagonal structure with alumina cylinders in air by reducing the symmetry of the structure.An instructive procedure is described for finding the optimal configuration which gives the maximum absolute bandgap Δω=0.091(2πc/α).  相似文献   
86.
A Kondo model in a square tight-bonding lattice of conduction electrons is considered.The Kondo interaction takes a d-wave.Using mean-field theory and numerical simulations,it is found that there is a pseudo-gap for the impurity density of states at the Fermi level.Numerical results also show that the exponents of the lowtemperature thermodynamic quantities are non-universal but dependent on the interaction.  相似文献   
87.
With an atomic force microscopy (AFM)tip used as a “nib” and gold colloidal particles as “ink”,patterns of gold colloidal particles have been deposited successfully from the AFM tip onto specific regions of silicon surfaces modified by bifunctional mercaptosilane,i.e.(3-mercaptopropyl)-triethoxysilane.This was used as an adhesion agent and can immobilize nanoparticles delivered from the AFM tip onto the substrate surface.  相似文献   
88.
The transition from the phase-unlocking state to the phase-locking state is found at the desynchronization of synchronous chaos of coupled oscillators.In the phase-locking case,the motions of all oscillators are chaotic and desynchronized,however spatial ordering is identified in their phase distribution.  相似文献   
89.
In the framework of the tight binding model,the electronic transmission properties of two-dimensional Penrose lattices with free boundary conditions are studied using the generalized eigenfunction method (Phys.Rev.B 60(1999)13 444).The electronic transmission coefficients for Penrose lattices with different sizes and widths are calculated,and the result shows strong energy dependence because of the quasiperiodic structure and quantum coherent effect.Around the Fermi level E=0,there is an energy region with zero transmission amplitudes,which suggests that the studied systems are insulating.The spatial distributions of several typical electronic states with different transmission coefficients are plotted to display the propagation process.  相似文献   
90.
We have measured the equation of state for liquid nitrogen compressed dynamically to a pressure of 10-60 GPa by employing a two-stage light-gas gun.The data show a continuous phase transition above the shock pressure of 33GPa,as indicated previously by shock wave experiments.A theoretical model has been derived to examine the experimental data by inducing a molecular dissociative fraction.According to theoretical and experimental date the phase transition was thought to be a molecular dissociative phase transition.  相似文献   
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