Five-beam Holographic Fabrication of 3D Photonic Crystal Templates Using a Single Diffractive Optical Element

摘要

In this paper we demonstrate an approach for laser holographic manufacturing of three-dimensional photonic lattice structures using a single specially designed, diffraction optical element mask. The mask is fabricated by recording gratings in a photosensitive polymer using a two-beam interference method and has four diffraction gratings in the sample plane, with a same distance from the opening center and oriented four-fold symmetrically. Four first-order diffracted beams by the gratings and one non-diffracted central beam overlap and form three-dimensional interference pattern. The phase of one side beam is delayed by inserting a thin piece of microscope glass slide into the beam. By rotating the glass slide thus tuning the phase of the side beam, the five beam interference pattern changes from face-center tetragonal symmetry into desired diamond-like lattice symmetry. The three-dimensional interference pattern is recorded in a photosensitive polymer, showing the phase tuning related changes of photonic lattice structures. Combing an amplitude mask with the phase mask by putting the amplitude mask in the central opening of the diffraction optical element mask, line defects are produced within the photonic crystal template.