Eur. Phys. J. B (2014) 87: 76
https://doi.org/10.1140/epjb/e2014-40737-9

Regular Article

Acoustic waves and phonon focus in Li crystal: the first principle study

¹ College of Physics and Electronic Information, Luoyang Normal College, Luoyang 471022, P.R. China
² State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, P.R. China
³ Department of Electronic Science, Xiamen University, Xiamen 361005, P.R. China
⁴ Electronic information engineering institute, Henan university of science and technology, Luoyang 71023, P.R. China

^a e-mail: fhzscdx@163.com

Received: 5 August 2013
Received in final form: 21 September 2013
Published online: 26 March 2014

Abstract

The acoustic waves in Li are investigated by solving the Christoffel equations. Theoretical calculations of the three dimensional slowness surfaces give insights into the mixing of longitudinal and transverse modes and show the origin of the phonon caustics. The results are explained in terms of phonon focusing due to the anisotropy of crystals. The propagation of elastic waves in Li is affected by the elastic anisotropy of the lattice.