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1.
The present work offers new equations for phase evaluation in measurements. Several phase shifting equations with an arbitrary but constant phase shift between captured intensity signs are proposed. The equations are similarly derived as the so-called Carré equation. The idea is to develop a generalization of Carré equation that is not restricted to four images. Errors and random noise in the images cannot be eliminated, but the uncertainty due to their effects can be reduced by increasing the number of observations. An experimental analysis of the mistakes of the technique was made, as well as a detailed analysis of mistakes of the measurement. The advantages of the proposed equation are its precision in the measures taken, speed of processing and the immunity to noise in signs and images. 相似文献
2.
D.L. Peng T.J. Konno K. Wakoh T. Hihara K. Sumiyama 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,16(1):329-332
Cluster-cluster coalescence process of monodispersed Co clusters with mean diameter d = 8.5 and 13 nm deposited a plasma-gas-condensation-type cluster beam deposition system was investigated by in situ electrical conductivity measurements and ex situ scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and analyzed by percolation concept. The electrical
conductivity measurement and TEM observation indicated that, below temperature T≈ 100°C, the Co clusters in the assemblies maintain their original structure as deposited at room temperature, while that the inter-cluster
coalescence takes place at T > 100°C, although the size distribution and the interface morphology of the clusters showed no marked change at substrate temperatures
T
s≤200°C.
Received 29 November 2000 相似文献
3.
M. Hiane J. Ebothé 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,22(4):485-495
We show that the electrodeposition of Ni-Zn alloys at the lowest growth velocities, v < 0.5μm/s, exclusively proceeds from an abnormal co-deposition phenomenon. The growth process in this v region greatly depends on the initial [Co2+] concentration of the film deposition bath. A theoretical approach of this process including the role of the saturation surface
roughness of the alloy, , leads to an estimation of the transport properties of the ad-atoms involved during the deposit formation. Their surface
diffusion coefficient varying between 1.76×10-10 and 2.40×10-8 cm-2/s exhibits a minimal value, D
s = 2.10×10-10 cm-2/s located between v = 0.17 and 0.35μm/s. The spatial scaling analysis of the local roughness, σ, examined according to the power-law σ≈L
α reveals that the resulting roughness exponents concurs with the Kardar-Parisi-Zhang dynamics including the restricted surface
diffusion. Two main v regions leads to different fractal textural features of the alloy film surface. Below 0.10 μm/s, the roughness exponent obtained
is α≈ 0.6, depicting a limited ad-atom mobility. Over v = 0.30μm/s, this exponent stabilises at α≈ 0.82, indicating an increase of the surface diffusion.
Received 16 August 2000 and Received in final form 20 June 2001 相似文献
4.
A novel method of virtual shearing interferometry (VSI) is proposed. In this method, the shearogram is obtained by interference of a real object wave-front and a virtual object wave-front. The former is optically recorded and then digitally reconstructed; and the latter is introduced digitally by repositioning or reforming the former. The obvious advantages of VSI over conventional shearing interferometry (SI) are its versatility, accuracy, and simplicity. Only one real field is necessary to produce shearogram; there is no need of any real shearing device or even the phase unwrapping computation; and the digital shear can take any possible form according to different purposes. Both the optical experiments and computer simulations with lateral shearing, 180° rotational shearing and double lateral shearing for evaluation of lens aberrations in the general case including spherical aberration, coma, astigmatism, defocus, and tilts based on phase-shifting interferometry are given to verify the effectiveness of this method. 相似文献
5.
Thin films of antimony doped tin oxide (SnO2:Sb) were prepared by spray pyrolysis technique using SnCl2 as precursor with the various antimony doping levels ranging from 1 to 4 wt%. The XRD analysis showed that the undoped SnO2 films grow in (211) preferred orientation whereas the Sb doped films grow in (200) plane. Scanning electron microscopy studies indicated that the surface of the films prepared with lower doping level (1 wt%) consists of larger grains whereas those prepared with higher doping levels (>1 wt%) consist of smaller grains. The sheet resistance has been found to be reduced considerably (2.17 Ω/□) for Sb doped films. To the best of our knowledge this is the lowest sheet resistance obtained for Sb doped SnO2 thin films. 相似文献
6.
ZnO nanotubes were successfully synthesized by a simple template-free hydrothermal method. X-ray powder diffraction and transmission electron microscopy were used to characterize the as-prepared ZnO nanotubes. The average size of the nanotubes is 200-500 nm in length and 20-30 nm in diameter. In addition, a further investigation of the optimized synthetic conditions has been carried out. 相似文献
7.
E. M. Azaroual P. Luc R. Vetter 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1992,24(2):161-164
The use of an effusive beam of titanium atoms crossed with a CW single-mode tunable dye laser has allowed the high-resolution, Doppler-free study of the isotope shifts between50Ti,48Ti and46Ti, for seven 3d
2 4s
2 a3
F
J
3d
2 4s 4p z
5
D
J
, visible transitions of Ti I. The measurements show without ambiguity the existence of a non-negligible field shift. Using the values of the nuclear radii of titanium (coming from muonic X-ray measurements), it is possible to determine the respective values of the field and mass shifts. 相似文献
8.
Mixed thin films of (CdO)1−x(PbO)x and (CdS)1−x(PbS)x (x=0.25) were prepared on glass substrates by spray pyrolysis technique for various substrate temperatures 300, 320 and 340 °C. Structural and optical properties were studied. XRD studies reveal the formation of mixed films. The substrate temperature of 340 °C seems to be critical for the formation of CdO-PbO mixed films. It is observed that (CdS)1−x(PbS)x mixed films were formed at all the three substrate temperatures. The direct band gap value of (CdO)1−x(PbO)x and (CdS)1−x(PbS)x mixed films is about 2.6 and 2.37 eV, respectively. 相似文献
9.
R. Mélin D. Feinberg 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(1):101-114
We derive a microscopic transport theory of multiterminal hybrid structures in which a superconductor is connected to several
spin-polarized electrodes. We discuss the non-perturbative physics of extended contacts, and show that such contacts can be
well represented by averaging out the phase of the electronic wave function. The intercontact Andreev reflection and elastic
cotunneling conductances are identical if the phase can be averaged out, namely in the presence of at least one extended contact.
The maximal conductance of a two-channel contact is proportional to (e
2/h)(a
0/D)2exp[-D/ξ(ω*)], where D is the distance between the contacts, a0 the lattice spacing, ξ(ω) is the superconducting coherence length, and ω* is the cross-over frequency between a perturbative regime ( ω < ω*) and a non perturbative regime ( ω* < ω < Δ).
Received 18 June 2001 and Received in final form 17 January 2002 相似文献
10.
Current partition in multiprobe conductors in the presence of slowly oscillating external potentials 总被引:2,自引:0,他引:2
In the presence of a static potential drop a carrier stream incident at a contact of the sample is partitioned into the other contacts according to the transmission probabilities of the sample. The bare response to oscillating potentials, on the other hand, violates current conservation due to the piling up of unscreened charges in the sample, and has to be modified by taking the induced screening potential into account. We present a novel derivation of the conductance response to oscillating external chemical potentials, find the response to an arbitrary internal potential in terms of functional derivatives with respect to the local potential of the scattering matrix of the conductor, and determine the screening potential for slowly oscillating potentials from the condition of local charge neutrality. We find that the current partitioning depends on ratios of local densities of states which reflect the injection and emission properties of the contacts of the sample. 相似文献