Investigation of optical inhomogeneities of multilayered reflecting coatings with high spatial resolution

An original method for the diagnostics of reflecting coatings is proposed. This method is applied to the investigation of multilayered mirrors used in laser gravitational antennas. The possible influence of the detected defects on the sensitivity of antennas is discussed.     

Source of reaction-diffusion coupling in confined systems due to temperature inhomogeneities

Diffusion is often accompanied by a reaction or sorption which can induce temperature inhomogeneities. Monte Carlo simulations of Lennard-Jones atoms in zeolite NaCaA are reported with a hot zone presumed to be created by a reaction. Our simulations show that localized hot regions can alter both the kinetic and transport properties. Further, enhancement of the diffusion constant is greater for larger barrier height, a surprising result of considerable significance to many chemical and biological processes. We find an unanticipated coupling between reaction and diffusion due to the presence of hot zone in addition to that which normally exists via concentration.     

The possibility of reconstruction of two-dimensional random inhomogeneities in a shallow sea by frequency shifts of the spatial interference structure of the sound field

Fluctuations of frequency shifts of the spatial interference structure of the sound field in the oceanic waveguide, caused by a two-dimensional field of a random perturbation, are described. Various schemes of observation point spacing are considered. The possibility is shown to reconstruct the spatial spectrum of waveguide perturbations by measuring the spatial spectrum of the frequency shift of the interference pattern. The results of the theoretical treatment are illustrated by the examples of background internal waves and bottom roughness. The sensitivity of monitoring based on measurements of frequency shifts of the interference structure of the sound field is estimated. For medium perturbations by background internal waves, the fluctuations of liquid layer vibrations, sound speed, and temperature, which are minimum detectable by frequency shifts of the interference pattern, were estimated.     

含定向非均匀体固体材料的横观各向同性有效弹性模量

针对非均匀体定向指向的情况,将非均匀体对弹性波的散射等效为球形有效体对弹性波的散射,推导出了呈现横观各向同性的有效弹性模量.理论分析表明:本文得到的有效模量公式至少具有二阶精度.数值计算表明:本文的有效模量随孔隙度增加而降低,不会出现Hudson模型中在孔隙度超过一定阈值后不减反增的问题.另外,在非均匀体指向随机的情况,本文得到的有效模量公式归结为Kuster-Toks z模型的公式.对于由扁状裂隙作为非均匀体的孔隙岩石,裂隙内液体主要影响横观各向同性对称轴方向的纵波模量.     

The measurement of the electrical field distribution by external electro-optic measuring system with submicrometre spatial resolution

A GaAs solid immersion lens has been applied to the external electric-optic measuring system. The spatial resolution of the system is improved to 0.7 μm because of the increased effective number aperture. We measured the electrical field distribution of ceramic microstrip lines transversely. The variation of electrical field with a submicrometre interval has been revealed experimentally and the results are in good agreement with the theoretical analysis.     

Resonance shifts in ABMR due to inhomogeneities of the magnetic and rf-fields

On the basis of the non-relativistic time dependent Schrödinger theory shifts of the resonance frequency due to an arbitrary inhomogeneity of the rf-field with respect to amplitude, direction and phase, and shifts due to small inhomogeneities of the magnetic field are considered. A general relation is derived by which one can find the appropriate experimental methods to determine the shifts without a detailed knowledge of the actual line shapes. Usually small effects as shifts due to non-constant field direction or due to neighbouring states are included in the formalism. The results have been used successfully in precision experiments in which frequency shifts of about 10^?2 of the resonance width were eliminated up to a few 10^?5.     

Method of measuring the spatial resolution of a photoresist

By analysis of the response of a high-contrast photoresist to sinusoidal illumination, generated interferometrically, one can extract a phenomenological modulation transfer function of the resist material, thereby characterizing its spatial resolution. Deep-ultraviolet interferometric lithography allows the resist response to be quantified at length scales below 100 nm. As an example, the resolution (FWHM) of the commercial resist UVII-HS is found to be approximately 50 nm. This simple method can be applied to materials under development for advanced photolithography with short-wavelength illumination.     

The Mössbauer effect as a means to detect gravitational waves

An experiment for the detection of gravitational waves is proposed which utilizes the Mössbauer effect. The theory behind this experiment is based on an alternate formulation of the special theory of relativity which is summarized here.     

The Pohlman cell as as a means of producing acoustic holograms

This paper reports the application of acoustic holography to a previously used non-destructive testing technique — the Pohlman Cell.