Title :
Observation and interpretation of mode splitting in positive rayleigh wave dispersion characteristics
Author :
Beldi, I. ; Hadjoub, Z. ; Doghmane, A. ; Gacem, A.
Author_Institution :
Dept. de Phys., Univ. Badji-Mokhtar, Annaba, Algeria
Abstract :
In this paper, we investigate the positive dispersive behavior of Rayleigh velocity for several layer/substrate combinations: Cr/quartz, SiO2/Mo, SiO2/stainless steel and Cr/Mo. The simulation conditions were those usually used in conventional acoustic microscopy. It was found that a second mode appears next to that of Rayleigh, unlike the usual unique dispersive curve. Moreover, this new mode has a negative dispersive behavior which is not likely to happen in the rigidity effect. This unusual phenomenon is interpreted by the acoustic impedance mismatching between layers and substrates.
Keywords :
Rayleigh waves; acoustic impedance; acoustic microscopy; chromium; silicon compounds; surface acoustic waves; Cr-Mo; Cr-SiO2; FeCCrJk; Mo; Rayleigh velocity; SiO2; SiO2-FeCCrJk; SiO2-Mo; acoustic impedance mismatching; acoustic microscopy; mode splitting; negative dispersive behavior; positive Rayleigh wave dispersion characteristics; rigidity effect; surface acoustic waves; Acoustic devices; Acoustic materials; Acoustic waves; Chromium; Dispersion; Frequency; Microscopy; Steel; Substrates; Water; Rayleigh velocity; acoustic impedance; acoustic microscopy; elastic parameters; layers;
Conference_Titel :
ICTON Mediterranean Winter Conference,2009. ICTON-MW 2009. 3rd
Conference_Location :
Angers
Print_ISBN :
978-1-4244-5745-8
Electronic_ISBN :
978-1-4244-5746-5
DOI :
10.1109/ICTONMW.2009.5385533
