Download or read book Study of the Dependence of Photoenhanced Nonlinear Acoustic Surface Wave Interactions on the Wavelength of Light written by Edgar A. Kraut and published by . This book was released on 1977 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of illumination with bandgap light on the convolution of surface acoustic waves on ZnO and GaAs has been investigated as a function of light wavelength and crystal temperature. The experiments indicate that the photoenhancement effect in ZnO is sensitive to trapping and surface preparation. A possible model for the dependence of photoenhancement on photon wavelength in ZnO has been proposed. Attempts to observe the photoenhancement effect in GaAs were unsuccessful because of problems in obtaining the correct sample resistivity. (Author).
Download or read book Research in Progress written by and published by . This book was released on 1975 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1977 with total page 1006 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Journal of the Acoustical Society of America written by and published by . This book was released on 1977 with total page 1334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1977 with total page 866 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1977 with total page 964 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acoustic Wave Semiconductor Convolver Applied to Electrical and Optical Signal Processing written by Herve Renson Gautier and published by . This book was released on 1975 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents an experimental and theoretical study of the interactions between acoustic surface waves on a piezoelectric insulator and charge carriers in a neighboring semiconductor separated by a small airgap; and the application of these phenomena to signal processing and optical imaging. Although the two media are mechanically isolated, the electric field associated with the surface waves penetrate into the semiconductor and interact with its charge carriers. This interaction is nonlinear, and, in the case of two oppositely propagating surface waves, real time convolution is performed. A new theory of the convolution interaction, taking into account the possible presence of a depletion, inversion or accumulation layer at the surface of the semiconductor, resulting from a built-in or applied dc field is presented. Experimental measurements for both n- and p-type Silicon on Lithium Niobate systems are in very good agreement with this theory, and they lead to a novel technique of measurement of the surface state distribution on semiconductors. The silicon on lithium niobate structure used gives rise to one of the largest convolution efficiencies reported to date. Several signal processing applications are presented. They show the versatility of the device which can be employed as a programmable filter or a parametric processor. In addition, the first autocorrelation is demonstrated by cascading two convolvers. The acoustic convolver was adapted for the scanning of optical images.
Download or read book Surface Waves in Solids written by E. G. Lean and published by . This book was released on 1971 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: The document discusses the results of the experimental and theoretical investigations of surface acoustic waves propagating on piezoelectric substrates. It includes the parametric interactions, harmonic generation, parametric mixing of surface acoustic waves, interactions between light and surface acoustic waves, and the excitation of acoustic surface waves by a grating coupled Gunn oscillator. The accomplished results are reported in four papers entitled (1) Harmonic generation of Rayleigh waves in LiNbO3 substrates with a thin film, (2) Nonlinear interaction of surface waves with pseudo-surface waves, (3) The light diffraction efficiency of acoustic surface waves, (4) Excitation of acoustic surface waves with a grating coupled Gunn oscillator. (Author).
Download or read book Nonlinear Acoustic Wave Interactions in Layered Media written by David Marvin Yeager and published by . This book was released on 1980 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: The conversion efficiency of parametric amplification in fluids is low because of the low dispersivity. A discontinuous change in phase velocity at the boundary of a waveguide introduces dispersion, which in turn affects conversion efficiency. It is the purpose of this thesis to develop from first principles an analytical model which may be used to numerically predict the conversion efficiency of a flat-plate, acoustic waveguide given the physical parameters of the system. In order to quantify weak, finite-amplitude interactions in the guide, the linear behavior of the system must first be analyzed. This is accomplished using Green's functions. Once the linear characteristics have been determined, nonlinear phenomena are investigated; both analytically and numerically via digital computer graphics. The physical parameters in the numerical examples were chosen to correspond with materials used in previously published experimental work using cylinders rather than flat plates. (Author).
Download or read book Studies of Acoustic Wave Phenomena for the Period September 1971 to August 1972 written by Stanford University. Microwave Laboratory and published by . This book was released on 1972 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acoustic Surface Wave and Acousto optic Devices written by Thomas Kallard and published by . This book was released on 1971 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of Nonlinear Interaction of Acoustic Waves with Application to Sound Reproduction written by Wei Guo Dong and published by . This book was released on 2000 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Studies of Acoustic Surface Wave Discontinuities written by Ronald Vernon Schmidt and published by . This book was released on 1971 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Depth Dependence and Some Anomalous Effects of Noise from Surface Wave Interaction written by Douglas H. Cato and published by . This book was released on 1993 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theories of sound generation by surface wave interaction usually calculate the far field noise, i.e., that applicable to receivers deep in the ocean, say 5000 m deep. Substantially higher noise levels are to be expected at receivers in the near field (depths up the several hundred metres). This paper compares the theoretical and measured depth dependence results. At 50 m depth, noise levels may be up to 20 dB higher than at 5000 m. The noise generated by wave interaction depends critically on the horizontal spread of surface wave energy. Measurements of this spread of energy are fairly consistent at high frequencies and wind speeds, and these are the values usually used to calculate the noise. As frequencies approach the spectral peak from above, the spread of energy decreases with the consequence that noise levels would be lower than predicted. Moreover, estimates of this spread vary over a wide range in the region of the spectral peak, sufficient to vary the predicted noise levels by about 40 dB. This may account for some of the observed variation in noise levels, however there remain some unresolved inconsistencies.
Download or read book Nonlinear Phenomena in Electromagnetic and Acoustic Wave Propagation written by J. B. Keller and published by . This book was released on 1984 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: We studied mathematical problems in electromagnetic and acoustic wave propagation which involve nonlinear partial differential equations, or linear partial differential equations with random coefficients. A general theory of weakly nonlinear high frequency wave propagation was developed which applies to waves in number of dimensions. It justifies the nonlinearization technique of Whitham and Landau and extends it to interacting waves and to other types of waves. The theory was successfully applied to weak shock diffraction. The theory of wave reflection from rough surfaces was extended to yield the correlation functions of the scattered field. It was found that the second order correlations could be expressed in terms of the reflection coefficient and the differential scattering cross section of the surface.
Download or read book On the Interaction of Acoustic Surface Waves with Thermal Phonons at Low Temperatures written by S. L. McBride and published by . This book was released on 1969 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Steady state Nonlinear Interactions of Surface Acoustic Waves written by Nickolas Peppino Vlannes and published by . This book was released on 1977 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt:
