Dipartimento di Fisica , Università della Calabria , Ponte P. Bucci 31C , 87036 Rende , CS , Italy.
CNR-Nanotec and Centre of Excellence CEMIF.CAL , Ponte P. Bucci 33B , 87036 Rende, CS , Italy.
ACS Appl Mater Interfaces. 2019 Sep 18;11(37):34471-34477. doi: 10.1021/acsami.9b12624. Epub 2019 Sep 5.
The capability to pattern polymer surfaces at different length scales is an important goal in different research fields, including display technologies, microelectronics, optics, as well as biorelated and medical science. However, the ability to optically and dynamically manipulate topography is a key feature enabling remote control of associated effects/processes mediated by the surface. Azopolymers are largely investigated to this aim based on their sensitivity to optical fields and reconfigurability capabilities. In this work, surface relief formation induced by polarization patterns on an amorphous azopolymer structurally engineered to have large photoinduced birefringence has been investigated both experimentally and theoretically. Based on the different light polarization patterns, depth and shape of the relief grating can be controlled. An optically induced gradient force model that includes both the spatial distribution and the anisotropy of the material permittivity has been theoretically analyzed. The proposed approach is able to explain the experimental results and to overcome the limitation of existing models.
在不同的研究领域中，对不同长度尺度的聚合物表面进行图案化的能力是一个重要目标，包括显示技术、微电子学、光学以及生物相关和医学科学。然而，光学和动态地操控形貌的能力是能够远程控制由表面介导的相关效应/过程的关键特征。基于其对光场的敏感性和可重构性，已广泛研究了偶氮聚合物以实现这一目标。在这项工作中，通过对结构工程设计具有大光致双折射的无定形偶氮聚合物的偏振图案，研究了表面浮雕的形成，从实验和理论两个方面进行了研究。基于不同的光偏振图案，可以控制浮雕光栅的深度和形状。理论上分析了一种包括材料介电常数的空间分布和各向异性的光致梯度力模型。所提出的方法能够解释实验结果，并克服现有模型的局限性。
