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941.
Influences of decoherence on the generation of a macroscopic superposition state using weak cross-Kerr effect 下载免费PDF全文
Considering a system in which a single photon and a coherent field
propagate through a Kerr medium, when the weak cross-Kerr
interaction between the coherent state and the single photon under
decoherence is involved, this paper derives analytically a
macroscopic superposition state by the superoperator method and
investigates the influences of decoherence on the coherence
properties of the obtained state. It finds that the macroscopic
superposition state will experience evolution from a pure
superposition state to a mixed state in a dissipative environment
and the Kerr effect makes the field display a periodic revival from
decoherence for a short time. 相似文献
942.
W. J. Xu B. Zhang Z. Wang S. S. Chu W. Li Z. B. Wu R. H. Yu X. X. Zhang 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(2):233-237
The scaling of anomalous Hall resistivity on longitudinal resistivity has been intensively studied in different magnetic systems,
including multilayer and granular films, to examine whether a skew scattering or a side jump mechanism dominates in the origin
of anomalous Hall effect (AHE). The scaling law is based on the premise that both resistivities are a consequence of electron
scattering by the imperfections in the materials. By studying the anomalous Hall effect in the simple Fe/Cu bilayers, it was
demonstrated that the measured anomalous Hall effect should not follow the scaling laws derived from skew scattering or side
jump mechanism due to the short-circuit and shunting effects of the non-magnetic layers. 相似文献
943.
A novel composite alkaline polymer electrolyte based on poly(vinyl alcohol) (PVA) polymer matrix, titanium dioxide (TiO2) ceramic fillers, KOH, and H2O was prepared by a solution casting method. The properties of PVA-TiO2-KOH alkaline polymer electrolyte films were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and AC impedance techniques. DSC and XRD results showed that the domain of amorphous region in the PVA polymer matrix augmented when TiO2 filler was added. The SEM result showed that TiO2 particles dispersed into the PVA matrix although some TiO2 aggregates of several micrometers were formed. The alkaline polymer electrolyte showed excellent electrochemical properties. The room temperature (20 °C) ionic conductivity values of typical samples were between 0.102 and 0.171 S cm−1. The Zn-Ni secondary battery with the alkaline polymer electrolyte PVA-TiO2-KOH had excellent electrochemical property at the low charge-discharge rate. 相似文献
944.
Ling Wu Xiaohua Yang Yangqin Chen 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(9):1586-1589
Thirty-four rovibronic spectral lines of the Ω=1/2 component of the (4, 8) band in the A-X system of 35Cl2+ were observed in the range of 16,940-17,010 cm−1, employing optical heterodyne-enhanced velocity modulation spectroscopy. Nonlinear least-squares fitting the effective Hamiltonians results in precise band origin and other molecular constants of the levels involved. 相似文献
945.
Self-imaging theory is widely accepted as a good method in designing 1 × N multimode interference (MMI) couplers, but it is also true that self-imaging theory is not suitable for low-contrast structures. An improved self-imaging theory is proposed in this paper for the optimal design of low-contrast 1 × N MMI couplers. The average effective width of MMI waveguide and the average effective propagation constant of MMI waveguide are used as the basis to modify the conventional self-imaging theory. A direct calculation of the average effective width of low-contrast MMIs is presented. We use this approach in the optimal design of a 1 × 4 silica MMI coupler, and the results show that the improved self-imaging theory is more accurate than conventional self-imaging theory for low-contrast structures, the results also show that if the material parameters and the width of an MMI waveguide are fixed, the average effective width of the MMI waveguide will increase with the decrease of the height of the core layer. 相似文献
946.
Realization of MMI Power Splitter by UV-light Imprinting Technique Using Hybrid Sol-Gel SiO2 Materials 下载免费PDF全文
An efficient fabrication scheme of buried ridge waveguide devices is demonstrated by UV-light imprinting technique using organic-inorganic hybrid sol-gel Zr-doped SiO2 materials. The refractive indices of a guiding layer and a cladding layer for the buried ridge waveguide structure are 1.537 and 1.492 measured at 1550nm, respectively. The tested results show more circular mode profiles due to existence of the cladding layer. A buried ridge single-mode waveguide operating at 1550 nm has a low propagation loss (0.088 dB/cm) and the 1× 2 MMI power splitter exhibits uniform outputs, with a very iow splitting loss of 0.029 dB at 1549nm. 相似文献
947.
In this work, the influence of Si/SiO2 interface properties, interface nitridation and remote-plasma-assisted oxidation (RPAO) thickness (<1 nm), on electrical performance and TDDB characteristics of sub-2 nm stacked oxide/nitride gate dielectrics has been investigated using a constant voltage stress (CVS). It is demonstrated that interfacial plasma nitridation improves the breakdown and electrical characteristics. In the case of PMOSFETs stressed in accumulation, interface nitridation suppresses the hole traps at the Si/SiO2 interface evidenced by less negative Vt shifts. Interface nitridation also retards hole tunneling between the gate and drain, resulting in reduced off-state drain leakage. In addition, the RPAO thickness of stacked gate dielectrics shows a profound effect in device performance and TDDB reliability. Also, it is demonstrated that TDDB characteristics are improved for both PMOS and NMOS devices with the 0.6 nm-RPAO layer using Weibull analysis. The maximum operating voltage is projected to be improved by 0.3 V difference for a 10-year lifetime. However, physical breakdown mechanism and effective defect radius during stress appear to be independent of RPAO thickness from the observation of the Weibull slopes. A correlation between trap generation and dielectric thickness changes based on the C-V distortion and oxide thinning model is presented to clarify the trapping behavior in the RPAO and bulk nitride layer during CVS stress. 相似文献
948.
Lead zirconate titanate (PZT) thin films are deposited on platinized silicon substrate by sol-gel process. The crystal structure and surface morphology of PZT thin films are characterized by X-ray diffraction and atomic force microscopy. Depth-sensing nanoindentation system is used to measure mechanical characteristics of PZT thin films. X-ray diffraction analyses confirm the single-phase perovskite structures of all PZT thin films. Nanoindentation measurements reveal that the indentation modulus and hardness of PZT thin films are related with the grain size and crystalline orientation. The increases of the indentation modulus and hardness with grain size are observed, indicating the reverse Hall-Petch effect. Furthermore, the indentation modulus of (1 1 1)-oriented PZT thin film is higher than those of (1 0 0)- and random-oriented films. The consistency between experimental data and numerical results of the effective indentation moduli for fiber-textured PZT thin films using Voigt-Reuss-Hill model is obtained. 相似文献
949.
Using the quantum hydrodynamic (QHD) equations with magnetic field on the Wigner-Maxwell system, the general dielectric tensor and dispersion equation for quantum plasmas were derived. Dispersion relations of one-, two-stream and beam-plasma instabilities in uniform quantum magnetized plasmas are investigated through the new dielectric tensor. The magnetic field which is parallel to the fluid velocity does not work on stream instabilities. The quantum and thermal effects have remarkable impact on two-stream instability. The critical wave number for beam-plasma instability with quantum effects correction is given too. 相似文献
950.
The mixed spin-1/2 and spin-1 Ising chain with both longitude and transverse single-ion anisotropies Dz and Dx is solved exactly by means of a mapping to the spin-1/2 Ising chain with the alternating transverse fields and the Jordan-Wigner transformation. The analytical expressions of the quasi-particles' spectra Λk, the minimal energy gap Δ0 for exciting a fermion quasi-particle, the minimal energy gap Δh for exciting a hole, and the ground state energy are obtained. The phase diagram of the ground state is also given. The results show that when Dz?0 for any finite value of Dx, there is no quantum critical point and the ground state is always in a spin ordered phase disregard of the boundary condition in the present system. 相似文献