温度変調ホットステージを用いた偏光顕微鏡観察

摘要

熱測定は，物性研究の最初の測定として非常に有用である。相転移の有無や，エントロピー変化から結晶の状態を判断するなど，簡単に全体像を把握することができる。しかし，温度と熱量の関係だけでは，試料内部で何が起 きているのかを把挺することは難しい。従って，詳細な観察のために，また研究の幅を広げるために，別の測定法を熱測定に組み合わせることも多い。%Temperature-modulated polarized light microscopy means the optical microscopy technique with the hot-stage by which the sample temperature is modulated periodically or step-like. Basic techniques for the temperature-modulated polarized light microscopy are summarized. The hot-stage was constructed using heating through light to give heat-flow modulation to the sample. The thermometer was put on the place which the heat reaches later than the sample. An example of application of the techniques to the studies of the phase transition of n-C_(36)H_(74) is described. The small crystal of n-C_(36)H_(74) was observed in the rotator phase transition temperature region. In the temperature region, the rotator phase coexists with the solid phase (low-temperature ordered phase). The boundaries of the two phases move reversibly with the temperature change. The area change of the rotator phase can be described by the Debye relaxation. The relaxation time agrees well with that of the dynamic specific heat.