Three-Dimensional Directional Assembly of Liquid Crystal Molecules.

The precise construction of hierarchically long-range ordered structures using molecules as fundamental building blocks can fully harness their anisotropy and potential. However, the three-dimensional (3D), high-precision, and single-step directional assembly of molecules is a long-pending challenge. Here, we propose a 3D directional molecular assembly strategy via femtosecond laser direct writing (FsLDW) and demonstrate the feasibility of this approach using liquid crystal (LC) molecules as an illustrative example. The physical mechanism for femtosecond (fs) laser-induced assembly of LC molecules has been investigated, and precise 3D arbitrary assembly of LC molecules has been achieved by defining the discretized laser scanning pathway. Additionally, an LC-based Fresnel zone plate array with polarization selection and colorization imaging functions has been fabricated to further illustrate the potential of this method. This study not only introduces a 3D high-resolution alignment method for LC-based functional devices but also establishes a universal protocol for the precise 3D directional assembly of anisotropic molecules. This article is protected by copyright. All rights reserved.