光束通过碘酸钾单晶产生的衍射花样及其与相变的依存关系

实验观察到了激光束通过KIO₃单晶时产生的偏振态改变90°的衍射带和衍射斑。研究了从室温到240℃温度范围内衍射光强随晶体温度的变化,当T=72℃时衍射光强突然急剧增加,T=212℃时衍射光强几乎减小到零,T>212℃时观察不到衍射光,72℃和212℃分别与有关文献报道的KIO₃的两个相变温度相同。 关键词：

THE DIFFRACTION PATTERNS PRODUCED BY A LASER BEAM PASSING THROUGH POTASSIUM IODATE CRYSTALS AND THEIR DEPENDENCE ON THE PHASE TRANSITIONS

In this paper, the diffraction bands and spots experimentally observed when a laser beam passed through a KIO₃ single crystal are reported. The bands and spots are formed by the diffracted beam, the plane of polarization of which rotates 90°with respect to that of the incident beam. The temperature dependence of the diffracted light was investigated in the region from room temperature to 240℃. It was found that when T=72℃ the intensity increased abrupty, when T=212℃ it decreased ;altnost to zero, and when T>212℃ no diffracted light was observed. The two temperatures, 72℃ and 212℃, determined from the anomaly of the intensity dependence, are in agreement very well with the phase transition temperatures of KIO₃ crystals reported in the literature.