Low-Temperature Measurement of the Hypersonic Absorption in Fused Quartz by Stimulated Brillouin Scattering

作者：W. Heinicke, G. Winterling, Klaus Dransfeld · 发表于：The Journal of the Acoustical Society of America · 年份：1971 · DOI：10.1121/1.1912455 · 被引用次数：32 · 研究领域：Seismic Waves and Analysis、Ultrasonics and Acoustic Wave Propagation、Thermography and Photoacoustic Techniques

By making use of stimulated Brillouin scattering, hypersonic absorption and velocity measurements in quartz glass were carried out at 24 GHz. Absorption data for longitudinal sound waves are presented below 8°K and velocity data between 4° and 300°K. The hypersonic absorption is observed to decrease strongly on cooling corresponding to a mean free path of the hypersonic phonons larger than 2 mm below 3.5°K. This value exceeds the mean free path calculated from heat conductivity data at 1.5°K for thermal phonons of similar energy by three orders of magnitude. The absorption data are discussed in connection with previous lower-frequency measurements.