-
通过用中子非弹性散射测量旋声晶体高对称方向的横声学支声子色散曲线的劈裂,从三个方面研究了同构异质晶体Bi12GeO20和Bi12SiO20的旋声特性。值得注意的是,沿〈111〉方向传播的左旋、右旋圆偏振声子具有不同的衰减。其中传播速度快的圆偏振声子衰减较大,该结论为这两种晶体所证实,这是在晶体旋声性研究中首次观察到的现象。实验还直接确定了衰减较大的这支声子的寿命约为2×10-11S。Acoustical activity of isomorphous crystals Bi12GeO20 and Bi12SiO20 has been studied by measuring the splitting of degeneracy of transverse acoustical waves propagating along high symmetric direction with inelastic neutron scattering. One of the interesting results is that the left and right circularly polarized modes of acoustical phonons propagating along direction are subjected to different attenuation. This conclusion is verified by both kinds of crystals. The experimental result is observed for the first time in the study of acoustical activity. The life-time of the phonon with larger attenuation is found to be about 2×10-11 s. experimentally.
计量
- 文章访问数: 6548
- PDF下载量: 681
- 被引次数: 0
下载:
