极化调节的状液晶相
D A Coleman1, J Fernsler, N Chattham
1Department of Physics and Ferroelectric Liquid Crystal Materials Research Center, University of Colorado, Boulder, CO80309 - 0390, USA.
概括
研究人员发现,流体极性状液晶可以克服内部挫折感. 这些材料表现出稳定,局部扩展的极化模式,形成独特的条纹和丝结构.
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
- 软物质物理学 软物质物理学
背景情况:
- 具有均偏振场的极性有序材料由于对非均局部偏振的对称性要求而经历内部挫折.
- 通常需要缺陷来实现局部极化扩散,但在常规铁电晶体和液晶中通常不稳定,导致全球丧.
研究的目的:
- 报告一种新型的流体极性状液晶类型,表现出稳定,不均的极化场.
- 研究这些材料中局部扩散的极化模式的形成和特征.
主要方法:
- 对流体极性状液晶的研究,这些液晶表现出周期性的超分子级极化调节条纹.
- 分析极化条和层波浪之间的合.
- 极地域的局部性和组织的表征.
主要成果:
- 确定了一类流体极性状液晶,在这些流体中,局部两极分离散层是稳定且普遍存在的.
- 这些材料显示周期极化调制条带与层波浪相结合.
- 极域表现出局部性,并被组织成交替的手性和极性模式,形成多样化的丝状和平面结构.
结论:
- 流体极性质液晶可以通过形成稳定,调节的极化场来克服极性材料的典型内部挫折.
- 观察到的流体层的波纹使复杂,有组织的结构的形成更容易,为材料设计提供了新的途径.
- 这些发现引入了在软物质系统中实现非均偏振的新范式.
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