On the effect of spatial dispersion on the degeneracies of acoustic-wave branches in crystals

@article{citeulike:702860, abstract = {The effect of spatial dispersion on the phase-speed degeneracies of acoustic waves in noncentrosymmetric crystals is explored in the framework of continuum elasticity. It is shown that the degeneracies, which in the nondispersive limit occur in directions neither lying in a symmetry plane nor parallel to a rotation inversion axis, are lifted on account of spatial dispersion. The degeneracies lying in symmetry planes change their in-plane orientation depending on the frequency, unless remaining fixed to a symmetry axis. Given that the degeneracy with regard for linear spatial dispersion occurs in some direction m, the value of degenerate phase speed coincides with the value of one of the speeds assigned to m in the nondispersive limit. Relations for the acoustic-wave parameters with dispersive corrections are derived and discussed for various particular cases. \©1998 Acoustical Society of America.}, author = {Shuvalov, A. L. }, citeulike-article-id = {702860}, doi = {10.1121/1.423715}, journal = {The Journal of the Acoustical Society of America}, keywords = {acoustics, axes}, number = {4}, pages = {2008--2014}, posted-at = {2006-06-20 14:22:48}, priority = {4}, publisher = {ASA}, title = {On the effect of spatial dispersion on the degeneracies of acoustic-wave branches in crystals}, url = {http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal\&id=JASMAN000104000004002008000001\&idtype=cvips\&gifs=yes}, volume = {104}, year = {1998} }

TY - JOUR ID - citeulike:702860 L3 - citeulike-article-id:702860 TI - On the effect of spatial dispersion on the degeneracies of acoustic-wave branches in crystals JF - The Journal of the Acoustical Society of America VL - 104 IS - 4 SP - 2008 EP - 2014 PB - ASA N2 - The effect of spatial dispersion on the phase-speed degeneracies of acoustic waves in noncentrosymmetric crystals is explored in the framework of continuum elasticity. It is shown that the degeneracies, which in the nondispersive limit occur in directions neither lying in a symmetry plane nor parallel to a rotation inversion axis, are lifted on account of spatial dispersion. The degeneracies lying in symmetry planes change their in-plane orientation depending on the frequency, unless remaining fixed to a symmetry axis. Given that the degeneracy with regard for linear spatial dispersion occurs in some direction m, the value of degenerate phase speed coincides with the value of one of the speeds assigned to m in the nondispersive limit. Relations for the acoustic-wave parameters with dispersive corrections are derived and discussed for various particular cases. ©1998 Acoustical Society of America. KW - acoustics KW - axes AU - Shuvalov, AL PY - 1998/// UR - http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JASMAN000104000004002008000001&idtype=cvips&gifs=yes ER -