Mostajeran Cyrus
Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Jun;91(6):062405. doi: 10.1103/PhysRevE.91.062405. Epub 2015 Jun 26.
In recent years there has been a growing interest in the study of shape formation using modern responsive materials that can be preprogrammed to undergo spatially inhomogeneous local deformations. In particular, nematic liquid crystalline solids offer exciting possibilities in this context. Considerable recent progress has been made in achieving a variety of shape transitions in thin sheets of nematic solids by engineering isolated points of concentrated Gaussian curvature using topological defects in the nematic director field across textured surfaces. In this paper, we consider ways of achieving shape transitions in thin sheets of nematic glass by generation of nonlocalized Gaussian curvature in the absence of topological defects in the director field. We show how one can blueprint any desired Gaussian curvature in a thin nematic sheet by controlling the nematic alignment angle across the surface and highlight specific patterns which present feasible initial targets for experimental verification of the theory.
近年来,利用现代响应材料研究形状形成引起了越来越多的关注,这些材料可以预先编程以经历空间不均匀的局部变形。特别是,向列型液晶固体在这方面提供了令人兴奋的可能性。最近,通过利用纹理表面上向列型指向矢场中的拓扑缺陷来设计集中高斯曲率的孤立点,在向列型固体薄片中实现各种形状转变方面取得了相当大的进展。在本文中,我们考虑在指向矢场中不存在拓扑缺陷的情况下,通过产生非局部化高斯曲率来实现向列型玻璃薄片形状转变的方法。我们展示了如何通过控制整个表面的向列型排列角,在薄向列型片中绘制出任何所需的高斯曲率,并突出显示了一些特定图案,这些图案为该理论的实验验证提供了可行的初始目标。