通过拉曼光谱学研究铁电阴性相中的秩序-混乱行为
Thomas Raistrick1, Richard J Mandle1,2, Zhaopeng Zhang1
1School of Physics and Astronomy, <a href="https://ror.org/024mrxd33">University of Leeds</a>, Leeds LS2 9JT, United Kingdom.
Physical review. E
|November 20, 2024
概括
研究人员使用拉曼光谱学研究了RM734中的铁电阴性相. 订单参数在N到N$_{F}$过渡附近下降,表明动态或极点订单开始的变化.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 物理化学 物理化学
背景情况:
- 极性顺序流体,包括铁电阴性相,具有重要的基本和应用兴趣.
- 了解铁电阴性材料的基本特性仍然是一个活跃的研究领域.
研究的目的:
- 使用拉曼光谱法,确定铁电阴性材料RM734的顺序参数.
- 为了研究铁电阴性液晶中的顺序参数和相变的行为.
主要方法:
- 拉曼光谱法用于测量顺序参数 (P2,P4) 和分析像全宽半最大 (FWHM) 这样的光谱特征.
- 双折度测量被用作一种补充技术来确认观察.
- 使用通常应用于固体铁电系统的框架分析了铁电阴性 (N$_{F}$) 过渡.
主要成果:
- 在N到N$_{F}$过渡附近观察到顺序参数 (ΔP2≈0.1,ΔP4≈0.06) 的减少和随后的恢复.
- 观察到拉曼峰FWHM (≈1 cm-1) 的扩大,与重定向动力学或极性顺序的出现有关.
- 量化了一种能量的障碍,使电转化为铁电 (≈2.5±0.6 kJ/mol),可与固体铁电相比较.
结论:
- 这项研究利用拉曼光谱学提供了对铁电阴性相的基本性质的见解.
- 观察到的顺序参数的下降归因于动态的变化或极点顺序的出现,而不是仅仅是分离波动.
- N$_{F}$过渡表现出类似于固体铁电材料过渡的特征.
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