Talbot effect from periodic and quasi-periodic structures: application to 3D quasi-crystalline photonic lattices formation

Abstract

We report the experimental investigation of image self-replication - Talbot effect with the use of 1- and 6 - fold rotational symmetry masks to create 3D intensity modulated light. These masks while having strong periodicity in azimuthal direction, are examples of multi-periodical and nearly periodical structures, respectively, along transverse XY directions. Since the Talbot image self-replication period in the axial direction depends on light wavelength and square of the structure periods, which are different in X-Y directions for 1-fold rotational symmetry mask, this gives a possibility to create the complex 3D light intensity distribution with different Talbot axial periodicity across the beam transverse plane. A cw single mode 532 nm, 100 mW laser beam was used in the experiment for formation of complex lattice beams. The observation of the transverse intensity patterns at multiple longitudinal positions will allow the construction of a whole 3D intensity distribution of the lattice beam. 3D intensity modulated light beams are promising for formation of crystalline and quasi-crystalline refractive index micro- and nano-structures in photorefractive materials.