optical branches

1

Phonons have complicated dispersion relations which generally have several acoustic and optical branches , the phonons in acoustic branches called acoustic phonons . The dispersion of acoustic phonons are linear around the center of the first Brillouin zone .

声学声子是声子的一个分支，它在第一布里渊区具有线性的色散关系，并且具有许多特性。
2

Some new configurations have been observed between the optical and acoustic branches which may be attributed to localized modes as a result of disorder .

另外，在光学支和声学支之间还测量出一些新的结构峰，估计是无序度造成的定域模。