Accession Number : ADA113312

Title :   Acoustic Microscopy at Cryogenic Temperatures.

Descriptive Note : Status rept. 1 Jul 81-1 Jan 82,

Corporate Author : STANFORD UNIV CA EDWARD L GINZTON LAB OF PHYSICS

Personal Author(s) : Quate,C F ; Heiserman,J

PDF Url : ADA113312

Report Date : Jan 1982

Pagination or Media Count : 54

Abstract : During this six month period we completed construction of a mechanical scanning device compatible with our dilution refrigerator and suitable for use at very low temperatures. This device has now been thoroughly tested and was used to record our first acoustic images in liquid helium at temperatures below 0.1 K. This report describes the design of the mechanical scanner and presents the first micrographs taken in this new regime of imaging. We also present theoretical results which account for much of the nonlinear imaging behavior described in the previous status report. In particular we investigate the theory of resolution improvement when high acoustic intensities are used, and quantitatively account for the onset of nonlinear excess attenuation. (Author)

Descriptors :   *Nondestructive testing, *Acoustic signals, *Microscopy, *Cryogenics, Images, Mechanical scanning, Resolution, Theory, Attenuation, Liquid helium, Nonlinear systems

Subject Categories : Printing and Graphic Arts
      Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE