Voloshinov Vitaly B, Polikarpova Nataliya V
Faculty of Physics, M. V. Lomonosov Moscow State University, Vorob'evy Gory, 119991 Moscow, Russia.
Appl Opt. 2009 Mar 1;48(7):C55-66. doi: 10.1364/ao.48.000c55.
The paper presents results on acousto-optic investigation of unusual acoustic phenomena taking place in crystals possessing strong anisotropy of elastic properties. Advantages of the applied method of analysis are demonstrated by the example of the commonly used acousto-optic material tellurium dioxide. The major goal of the research consists of experimental verification of theoretical conclusions related to peculiar cases of acoustic propagation and reflection recently observed in the crystalline material. In particular, the case of glancing incidence and the following reflection of elastic energy from a free boundary separating the paratellurite crystal and the vacuum is examined in the paper. It is shown in the acousto-optic experiment that, in the case of glancing incidence, energy flow of a reflected acoustic wave may propagate practically in a reverse direction with respect to an incident wave. It is also proved that strong elastic anisotropy of the crystal is responsible for the unusual propagation and reflection of the acoustic waves. The research confirms the conclusion that the examined acoustic effects may be useful in development of new acousto-optic devices.
本文介绍了对具有强弹性各向异性的晶体中发生的异常声学现象进行声光研究的结果。以常用的声光材料二氧化碲为例，展示了所应用分析方法的优势。该研究的主要目标是对近期在晶体材料中观察到的与声学传播和反射特殊情况相关的理论结论进行实验验证。特别是，本文研究了掠入射以及弹性能量从分隔副碲酸盐晶体和真空的自由边界反射的情况。声光实验表明，在掠入射的情况下，反射声波的能量流实际上可能相对于入射波沿相反方向传播。还证明了晶体的强弹性各向异性是声波异常传播和反射的原因。该研究证实了所研究的声学效应可能有助于新型声光器件开发的结论。
