薄膜成長技術を用いた対称性・不均一性の制御による非平衡臨界現象の実験的探求

利用薄膜生长技术控制对称性和不均匀性对非平衡临界现象的实验探索

• 批准号: 16J06923
• 负责人: LISBOA ALMEIDA RENAN AU
• 金额: $ 1.79万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2016
• 资助国家: 日本
• 起止时间: 2016-04-22 至 2019-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16J06923/
• 关键词: Statistical physics; Nonequilibrium; Coarsening; Model A; Percolation; Liquid crystal; Electroconvection; Liquid crystals; Thin films; Surface growth; statistical physics; phase transition; non-equilibrium; liquid crystal; surface alignment

Kinetic ordering in twisted nematics (TN) was studied by electrically-driven a two-dimensional TN layer from a nematic-disordered phase towards nematic-ordered phases. Several types of two-dimensional ordering dynamics were induced by controlling the final driving voltage. Dynamics related to a null driving voltage proceed by following universal model A scaling laws. Spatiotemporal correlation functions agree with approximate model A continuum theories. Temporal autocorrelation function decays as predicted by the Ohta-Jasnow-Kawasaki model, instead of the more accepted Mazenko's theory of unstable growth. A comprehensive study of additional model A aspects were experimentally analysed and confirmed. Recent theoretical results about the coexistence of critical percolation (CP) in the two-dimensional model A dynamics were investigated. An exact formula accounting for the number density of hull areas, proposed from CP results, was experimentally confirmed in its full range for the first time. A new CP-dynamic exponent, hitherto observed only in discrete model systems, was measured experimentally. These results confirm the unexpected emergence of CP in model A dynamics and imply a generalisation of the scaling hypothesis for coarsening theories.

采用电驱动的方法，研究了二维扭曲向列相的向列无序相向列有序相的动力学有序性。通过控制最终驱动电压，产生了几种二维有序动力学。与零驱动电压相关的动力学遵循通用a型标度定律。时空相关函数符合近似模型A连续体理论。时间自相关函数的衰减是由Ohta-Jasnow-Kawasaki模型预测的，而不是更被接受的Mazenko的不稳定增长理论。对模型A附加方面的综合研究进行了实验分析和验证。对二维模型A动力学中临界渗流共存的最新理论结果进行了研究。根据CP计算结果，提出了一个精确的船体区域数密度计算公式，并首次在全范围内得到了实验验证。一个新的cp动态指数，迄今为止只观察到在离散模型系统，测量实验。这些结果证实了模型A动力学中CP的意外出现，并暗示了粗糙化理论的标度假设的推广。

项目成果

Universal relaxation in phase-ordering kinetics of liquid crystals quenched from an electrohydrodynamic turbulent state

从电流体动力学湍流状态淬灭的液晶相序动力学的普遍弛豫

• 发表时间: 2018
• 作者: R. A. L. Almeida;K. A. Takeuchi
• 通讯作者: K. A. Takeuchi

Renan Augusto Lisboa Almeida - Lattes website

Renan Augusto Lisboa Almeida - 拿铁网站

Experimental Evidence of (2+1)-Dimensional Kardar-Parisi-Zhang Fluctuations in Semiconductor Films

半导体薄膜中 (2 1) 维 Kardar-Parisi-Zhang 涨落的实验证据

• 发表时间: 2016
• 作者: R. A. L. Almeida;S. O. Ferreira;and T. J. Oliveira
• 通讯作者: and T. J. Oliveira

The Kardar-Parisi-Zhang Universality Class

Kardar-Parisi-Zhang 通用班

• 发表时间: 2016
• 作者: R. A. L. Almeida;S. O. Ferreira;and T. J. Oliveira;R. A. L. Almeida
• 通讯作者: R. A. L. Almeida

Universidade Federal de Vicosa(Brazil)

维科萨联邦大学（巴西）