Trial construction of a non-contacting measurement system of elastic constants for tiny crystals

研制了一种测量微小晶体弹性常数的新装置。appa速率基于布里渊散射，布里渊散射经常用于测量非金属材料，例如陶瓷或有机材料。目前测量布里渊散射的仪器大多采用体积很大的氩离子激光器，要获得足够的输出功率需要相当大的功率。我们采用了一种新型光源，即二极管泵浦固体激光器，它具有体积小、电光转换效率高的特点。光源对布里渊散射最重要的一点是光的线宽（纯度）。我们检查了纯度，确认线宽足够窄，可以进行布里渊散射。仪器的另一个关键部分是光探测器；探测器必须具有高灵敏度、稳定性和低噪声的特点。光电倍增器常用于探测器，但传统的光电倍增器量子效率较低。我们采用了一种新型的光倍增器，它具有不同的材料来发射，对于532nm的光，我们的量子效率高达40%左右。使用这些新开发的部件，我们成功地构建了一个体积小，效率高的新装置

A new apparatus for measuring elastic, constants of tiny crystals has been developed. The appa rates is based on the Brillouin scattering that is frequently applied to the measurement of non-metallic materials, for example ceramics or organic materials. The most of apparatus for measuring the Brillouin scattering in uses Ar-ion laser that has very large volume and electrical power required is quite large to obtain enough output power. We adopt a new light source that is diode pumped solid state (DPSS) laser, which has very small volume and high efficiency of conversion from electrical to light. The most important point of the light source for the Brillouin scattering is the line width (purity) of the light. We have checked the purity and confirmed that the line width is enough narrow for the Brillouin scatteringAnother key part of the apparatus is light detector ; the detector must has high sensitivity, stability and low noise feature. A photo multiplier is frequently used to the detector, however, conventional one has low quantum efficiency. We adopt a new type of photo multiplier that has a different material to emitter with high quantum efficiency of about 40% for the light of 532nmBy using such newly developed parts, we have succeeded to construct a new apparatus having small volume and high efficiency