Tunable Surface Patterning of Azopolymer by Vectorial Holography: The Role of Photoanisotropies in the Driving Force.

ACS Appl Mater Interfaces

Dipartimento di Fisica , Università della Calabria, Ponte P. Bucci 31C , 87036 Rende , CS , Italy.

Published: September 2019

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.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.9b12624DOI Listing

Publication Analysis

Top Keywords

polarization patterns
8
tunable surface
4
surface patterning
4
patterning azopolymer
4
azopolymer vectorial
4
vectorial holography
4
holography role
4
role photoanisotropies
4
photoanisotropies driving
4
driving force
4

Similar Publications

High-pressure and low-temperature structural changes in the ferroelectric phase of (R)-3-quinuclidinol are analysed. The changes in unit-cell volume and parameters are continuous both on cooling and under increasing pressure. The anisotropy of the structural strain, however, is found to be different.

View Article and Find Full Text PDF

Sensing light's polarization and wavefront direction enables surface curvature assessment, material identification, shadow differentiation, and improved image quality in turbid environments. Traditional polarization cameras utilize multiple sensor measurements per pixel and polarization-filtering optics, which result in reduced image resolution. We propose a nanophotonic pipeline that enables compressive sensing and reduces the sampling requirements with a low-refractive-index, self-assembled optical encoder.

View Article and Find Full Text PDF

In the early Drosophila embryo, germband elongation is driven by oriented cell intercalation through t1 transitions, where vertical (dorsal-ventral aligned) interfaces contract and then resolve into new horizontal (anterior-posterior aligned) interfaces. Here, we show that contractile events produce a continuous "rectification" of cell interfaces, in which interfaces systematically rotate toward more vertical orientations. As interfaces rotate, their behavior transitions from elongating to contractile regimes, indicating that the planar polarized identities of cell-cell interfaces are continuously re-interpreted in time depending on their orientation angle.

View Article and Find Full Text PDF

Integration of Asymmetric Multi-Path Hollow Structure and Multiple Heterogeneous Interfaces in FeO@C@NiO Nanoprisms Enabling Ultra-Low and Broadband Absorption.

Small

January 2025

Key Laboratory of Aerospace Materials and Performance (Ministry of Education) School of Materials Science and Engineering, Beihang University, No.37 Xueyuan Road, Beijing, 100191, P. R. China.

A reasonable construction of hollow structures to obtain high-performance absorbers is widely studied, but it is still a challenge to select suitable materials to improve the low-frequency attenuation performance. Here, the FeO@C@NiO nanoprisms with unique tip shapes, asymmetric multi-path hollow cavity, and core-shell heteroepitaxy structure are designed and synthesized based on anisotropy and intrinsic physical characteristics. Impressively, by changing the load of NiO, the composites achieve strong absorption, broadband, low-frequency absorption: the reflection loss of -55.

View Article and Find Full Text PDF

The past decade witnessed a surge in discoveries where biological systems, such as bacteria or living cells, inherently portray active polar or nematic behavior: they prefer to align with each other and form local order during migration. Although the underlying mechanisms remain unclear, utilizing their physical properties to achieve controllable cell-layer transport will be of fundamental importance. In this study, the ratchet effect is harnessed to control the collective motion of neural progenitor cells (NPCs) in vitro.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!