低电场电热效应在同otropic-ferroelectric nematic 阶段过渡中的低电场电热效应
A Adaka1,2, P Guragain3, K Perera1,4
1Advanced Materials and Liquid Crystal Institute, Kent State University, Kent, OH, 44242, USA. ajakli@kent.edu.
Soft matter
|December 23, 2024
概括
这项研究证明了铁电阴性液晶中的电热效应 (ECE),使低电场的高效相位过渡成为可能. 减少离子含量可以提高ECE,为先进的固态冷却技术铺平道路.
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
- 热力学是一种热力学.
背景情况:
- 固态材料中的电热效应 (ECE) 对于开发高效的固态冷却系统至关重要.
- 现有的ECE研究主要集中在铁电陶和聚合物上.
研究的目的:
- 为了研究ECE在新合成的铁电阴性液晶化合物中.
- 探索使用ECE在低电场下的液晶中诱导相变的可行性.
主要方法:
- 在同otropic-ferroelectric nematic (I-NF) 阶段过渡时在铁电阴性液晶中对 ECE 的表征.
- 应用直流和交流电场来观察ECE和光传输率的变化.
- 过渡温度变化和EC响应性的分析.
主要成果:
- 在直流电场下,焦尔热抑制了ECE.
- 交流电场 (E < 1.2 V μm-1 , f ≥ 40 Hz) 诱导了可观测的ECE,改变了过渡温度.
- 测量了EC响应度的~1.7 × 10−6 公里V−1.
- 所需的电场比其他EC材料低两倍.
- 减少离子含量通过抑制焦尔热来增加了EC特异能.
结论:
- 铁电阴性液晶在低电场下表现出独特的EC效应.
- 在这些材料中,ECE可以有效地诱导相变.
- 通过减少离子含量来进一步优化可以提高冷却性能.
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