Generation of over 1000 Diffraction Spots from 2D Graded Photonic Super-Crystals

• DOI: 10.3390/photonics7020027
• Publication Date: 2020-04-13T08:45:31Z
• Authors: Safaa Hassan; Yan Jiang; Khadijah Alnasser; Noah Hurley; Hualiang Zhang; Usha Philipose; Yuankun Lin
• Keywords: Lattice constant

For the first time, we are able to generate over 1000 diffraction spots from a graded photonic super-crystal with unit super-cell size of 12a × where is lattice constant and hole radii gradually changed in dual directions. The pattern reveals unique properties. order diffractions (±1,0) or (0,±1) disappear. Fractional orders observed inside square vertices (1,1), (1,−1), (−1,−1) (−1,−1). fractional can be understood lattices period a. However, dual-lattice model considered explain higher-order diffractions. E-field intensity simulations show coupling re-distribution among Bloch waves. There total 12 supercell corresponding momentum Brillouin zone k-space.