The Lifetime of Thermal Phonons in α-Quartz

Abstract

<p>The attenuation of thermal phonons and acoustically generated phonons at different power levels are compared in α-quartz. The average attenuation at 1.67 GHz at room temperature was 27.3 db/cm ± 2.7% and at a frequency of 1.856 GHz, it was 32.5 db/cm ± 2.1%. Woodruff and Ehrenreich's theory was used to calculate the lifetime of thermal phonons from acoustic attenuation data. The relaxation time for thermal phonons at 300ºK was found to be 8.34x10‾¹² sec.</p>