Large negative Goos-H(a|¨)nchen shift from a wedge-shaped thin film

The analytical expression for the complex amplitude of light reflected from a wedge-shaped thin film is derived. For plane wave incidence, a simple ray tracing approach is used to calculate Goos-H(a|¨)nchen (GH) shifts; and for non-plane wave incidence, for example, a Gaussian beam, the angular spectrum approach of plane wave is used in simulation. The two approaches predict that a wedge-shaped thin film can produce large negative longitudinal GH shifts. Although the reflectivity is small near the condition...     

Green’s function for an electron model with a plane wave

The Green function for a Dirac particle subject to a plane wave field is constructed according to the path integral approach and the Barut’s electron model. Then it is exactly determined after having fixed a matrix U chosen so that the equations of motion are those of a free particle, and by using the properties of the plane wave and also with some shifts.      

Pure elastic resonance scattering of an obliquely incident plane acoustic wave by a submerged infinite cylinder

I.IntroductionTheResonanceScattcringThcory(RST)asanimportantmethodtoana1yzeacousticscat-teringofsubmergede1asticbodieswascxtcnsivelyuscdforcy1indrica1andspherica1geometries,inc1udingsolidstructuresandho11owoncs.RSTismain1yappliedtostudytheresonancescat-teringspcctra(oracousticspcctra)ofanc1astictargctcxcitedby'theinciderttacousticwavesoastOidentifythetargct.Tocxtracttheresonancescattcringspcctra,anappropriatebackgroundsuchasrigidbackgroundorsoftonemust-besubtractcd.Expcrimenta1ly,theReson…     

Readout of super-resolution marks with Ti thin film

Using Ti as the super-resolution reflective film to replace the Al reflective layer in conventional read-only optical disk, the recording marks with a diameter of 380 nm and a depth of 50 nm are read out in a dynamic testing device whose laser wavelength is 632.8 nm and numerical aperture of the lens is 0.40. The optimum Ti thin film thickness is 18 nm and the corresponding signal-noise-ratio is 32 dB.     

Elastic wave scattering from rough free surfaces of solids

Elastic wave scattering by a rough free surface of solids is analyzed. The analysis is based on the concept of scattering amplitude (SA) and perturbation approximation. The SA method is very convenient for rough surface scattering problems. By solving the boundary equations, the first and the second order solutions of approximate scattering amplitude are obtained. The general solutions are used for, as an example, the wave scattering by rough surfaces with Gaussian distribution. The mean field and variance are given. Finally, an experiment is designed to verifv the theoretical predications.     

Ultrasonic wave scattering in a fiber reinforced composite

I.IntroductionWiththerapiddevelopmentoffiberreinforeedcompositematerials,muchattcntionhasbeenpaidtothecva1uationofthefiber/matrixinterfaces[1-51wheredefectSmayemergeafterlongusageofthecomposites.Foraweakenedinterface,twostiffnessconstantsareusuallyin-tfoducedtomodc1theboundaryconditionsforthestressesanddisNacementsatbothsidesandtheyareclose1yrclatedtotheultrasonicattenuationduetoscattering['].However,sofarnopublishedrcportsarcavai1ab1e.Whitemadeadetailedinvestigationofsoundwavescatteringatac…     

The instability of electrostatic wave in a magnetized dusty plasma with nonadiabatic dust charge fluctuation

The effects of external magnetized field and nonadiabatic dust charge fluctuation on instability of wave incorporating the nonthermally distributed ions and the temperatures of ion and dust in dusty plasmas are investigated. A linear dispersion relation is obtained. The numerical results show that the external magnetized field, fast ions and nonadiabatic dust charge fluctuation have strong influence on the frequency and the damping of wave.     

Nonlinear optical properties of a self-organized dye thin film

A self-organized thin film of a cyanine dye is fabricated by the spin-coating technique and is characterized by ultraviolet-visible spectroscopy,infrared(IR)spectroscopy,small-angle X-ray diffraction,ellipsometer, and atomic force microscopy(AFM).The nonlinear optical properties of the thin films are investigated by degenerate four wave mixing(DFWM)technique.The cyanine dye thin film sample exhibits high optical nonlinearities(X~(3)=2.55×10~(-12)esu),and the mechanism is analyzed by the exciton coupling theory.     

Depolarization of backscattered linearly polarized light from ZnO thin film

The depolarization behavior of backscattered linearly polarized light from ZnO thin film was investigated experimentally.The results show that the characteristics are related to both the polarization orientation and wavelength of linearly polarized incident light.When the incident light is s-polarized,the depo- larization behaviors are different for different wavelengths.When the incident light is p-polarized,the depolarization behaviors,on the contrary,are similar for different wavelengths.In addition,there is an optimal incident angle for depolarization of linearly polarized light with different wavelengths,which is equal to their effective Brewster angles,respectively.     

The measurement of bending wave intensity in a two-dimensional structure

I.IntroductionOfallstructuralwaves,bendingwaveismostimportant.Itiseasilyexcitedandresultsinairbornenoiseradiation'Inpractice,itisnecessarytodeterminetheenergydistributionandpowertransmissionincoupledstructl1res.Bendingwaveenergycanbecalculatedfrombendingwaveaccelerationwhilebendingwavepowertransmissionischaracterizedbybendingwaveintensitywhichisavectorgivillgthemagnitudeanddirection.TheengineeringaPplicationofthevectorpropertyofbendingwaveilltensityisnumerous[1~3]buttheinvestigationinitispre…     

Quintessence Cosmology with a Coupled Real Scalar Field

In the light of the recent observations of type Ia supernovae (SNe Ia) suggesting an accelerating Universe,we show the possibility of a coupled real scalar field to be quintessence for the source of the accelerating Universe.We derive the main equations which govern the evolution of the Universe and rewrite them with the observable quantities.Finally we point out very briefly how future observations may determine the equation of state of quintessence.     

Interaction of a neutrino with a circularly polarized plane wave accompanied by (n¯n) pair production

We consider the processes (n )and n , induced by the interaction of the anomalous magnetic moment of the neutron with the field of a circularly polarized plane wave. Using the invariant solution of the modified Dirac equation, we obtain expressions for the total probabilities of these processes, which consist of several different contributions. The asymptotic behavior of the results at high energy is analyzed and the possibility of observing the effects is discussed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 46–53, July, 1990.The authors thank V. G. Bagrov for useful discussions.     

Visible electroluminescence from p-n junction porous Si diode with a polyaniline film contact

We have fabricated a light emitting diode using a p-type conducting polyaniline layer deposited on a n-type porous silicon (PS) layer. The contact formed between a p-type conducting polyaniline layer and a n-type PS wafer has rectified behaviour demonstrated clearly by the I-V curves. The series resistance Rs in the p-type conducting polyaniline/n-PS diode is reduced greatly and has a lower onset voltage compared with ITO/n-PS diode. The PS has an orange photoluminescence (PL) band after coating with polyaniline. Visible electroluminescence (EL) has been obtained from this junction when a forward bias is applied. The emission band is very broad extending from 600-803 nm with a peak at 690 nm.     

Scalar Perturbations in a Two-Component σ-Model with a Self-Action Potential

The evolution of cosmological scalar perturbations in a two-component -model with a self-action potential is examined for the class of models ensuring a power-law inflation. Solutions for perturbations of the metric in short- and long-wavelength approximations are derived.     

Acoustic scattering from multiple spheres by using a kind of addition formulae for the spherical wave functions

A kind of addition formulae for the spherical wave functions is generated by using the bicentric expansion of Green function in spherical coordinates. For an acoustical system with multiple spheres, the addition formulae permit the field expansions all referred to the center of one of the spheres, whose boundary conditions can be consequently used to study the multiple scattering easily. The two-sphere acoustical system with different boundary conditions is considered and the field scattered by each sphere can be obtained by solving an infinite set of two linear, complex, algebraic equations, whose coefficients are coupled through double sums in the spherical wave functions. Finally, the form functions of two spheres insonified by a plane wave at arbitrary angles of incidence are calculated and the addition formulae presented are validated by comparing the corresponding numerical results with those of the existing literature.     

Spin-dependent Fabry-Pérot interference from a Cu thin film grown on fcc Co(001)

Spin-dependent electron reflection from a Cu thin film grown on Co/Cu(001) was investigated using spin-polarized low-energy electron microscopy (SPLEEM). Fabry-Pe rot type interference was observed and is explained using the phase accumulation model. SPLEEM images of the Cu overlayer reveal magnetic domains in the Co underlayer, with the domain contrast oscillating with electron energy and Cu film thickness. This behavior is attributed to the spin-dependent electron reflectivity at the Cu/Co interface which leads to spin-dependent Fabry-Pe rot electron interference in the Cu film.     

Ideal fluid with the equation of state ε=p in the field of a plane gravitational wave

An exact solution of the equations of relativistic hydrodynamics is obtained for a semiinfinite ideal fluid with the equation of state =p in the field of a plane gravitational wave.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 99–102, November, 1982.     

Study on optical wave scattering from slightly Gaussian rough surface of layered medium

The optical wave scattering from the slightly rough surface of three-layer medium is studied.The formulaes of the scattering coefficients for different polarizations are derived using the small perturbation method. A Gaussian rough surface is presented for describing rough surface of layered medium,the influence of the permittivity of layered medium,the mean layer thickness of intermediate medium,the surface roughness parameters and the incident wavelength on the bistatic scattering coefficient of HH polarization are obtained and discussed by numerical implementation.