Photofabrication of three-dimensional photonic crystals by multibeam laser interference into a photopolymerizable resin

Abstract

Three-dimensional (3D) photonic crystalstructures can be fabricated into photopolymerizable resins by using laser beam interference with high precision. Three laser beams interfere into a glass cell filled with a liquid photopolymerizable resin to form a hexagonal periodic structure. Rods are formed in a hexagonal arrangement after being photopolymerzed according to the 3D periodic light distribution which results from the laser’s interference. Two beams of another laser also interfere to form layers which cross perpendicular to the rod array. After photofabrication, the nonsolidified resin is removed by ethanol. The lattice constant can be selected by tuning the angles of the incident beams and the laser wavelength. We have fabricated a 500 μ m ×500 μ m ×150 μ m photonic crystalstructure, the lattice constant of which is 1 μm and contains 150 lateral layers.