Theoretical analysis of acoustic attenuation and nonlinearity in barium monochalcogenides in B2 phase

• Published in: Turkish journal of physics Vol. 32; no. 4; pp. 211 - 218
• Main Authors: CHAURASIA, Sujeet Kumar, SINGH, Rishi Pal, SINGH, Rajendra Kumar, SINGH, Manish Pratap
• Format: Journal Article
• Language: English
• Published: TÜBİTAK 01-01-2008
• Subjects: acoustic attenuation; Akustik sönüm; Atomlar ve Moleküller; Atoms and Molecules; barium; Baryum; chalcogenide; Genel Fizik ve Temel Fizik; Kalkojenit; p-p etkileşimi; p-p interaction; Physics in General and Fundamental Physics; ultrasonic attenuation; Ultrasonik sönüm
• ISSN: 1300-0101

Temperature dependence of ultrasonic attenuation due to phonon-phonon interaction and thermoelastic
loss have been studied in (CsCl-type) barium monochalcogenides (BaX, X= S, Se, Te), in the
temperature range 50-500 K; for longitudinal and shear modes of propagation along <100>, <110> and
<111> directions. Second and third order elastic constants have been evaluated using electrostatic and
Born repulsive potentials and taking interactions up to next nearest neighbours. Gruneisen parameters,
nonlinearity constants, nonlinearity constants ratios and viscous drag due to screw and edge dislocations
have also been evaluated for longitudinal and shear waves at 300 K. In the present investigation, it
has been found that phonon-phonon interaction is the dominant cause for ultrasonic attenuation. The
possible implications of the results have been discussed.