具有C_{1h}对称性的铁电混凝土C_{F}相的宏观动力学
Harald Pleiner1, Helmut R Brand1,2
1Max Planck Institute for Polymer Research, 55021 Mainz, Germany.
Physical review. E
|December 23, 2025
概括
我们描述了 ferroelectric smectic C (SmC_{F}) 液晶的宏观动态,揭示了独特的交叉合条款和由于单临床对称性的双轴声速. 这些发现增强了对铁电液晶行为的理解.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 软物质物理学 软物质物理学
- 液晶是一种液晶.
背景情况:
- 铁电粘性C (SmC_{F}) 液晶表现出相对于正常层的倾斜极化 (P).
- 该相在空间均极限中具有C_{1h}对称性,使其与非极性微观C相区别开来.
研究的目的:
- 导出和分析SmC_{F}液晶的宏观动态方程.
- 阐明新的交叉合术语及其对材料性能的影响.
主要方法:
- 线性不可逆热力学和对称论证的应用.
- 在低频率和长波长时有效的动态方程的导出.
主要成果:
- 在层压缩和曲之间确定两个静态交叉合项,从而产生弹性应力,而不是力.
- 在SmC_{F}中发现了独特的静态交叉合项,由于平面内极化,在铁电A_{F}相中缺席.
- 证明声速 (第一个和第二个声音) 是双轴的,反映了单临床对称性.
- 对涉及流量,电场和梯度的可逆交叉合项的分析,以及层曲和温度梯度之间的散射合.
结论:
- 这项研究为了解SmC_{F}液晶的宏观动态提供了一个全面的框架.
- 发现了新的交叉合现象,为实验研究和材料设计提供了新的途径.
- 这些发现强调了单临床对称性和极化对这些材料动态反应的重大影响.
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