Title :
All-Angle Quasi-Self-Collimation Effect in a Rod-Type Silicon Photonic Crystal
Author :
Ming Li ; Wei Li ; Haiyang Huang ; Jing Wang ; You Li ; Aimin Wu ; Zhen Sheng ; Xi Wang ; Shichang Zou ; Fuwan Gan
Author_Institution :
State Key Lab. of Functional Mater. for Inf., Shanghai Inst. of Microsyst. & Inf. Technol., Shanghai, China
Abstract :
By changing the symmetry of a photonic crystal (PC) with a rectangular lattice to straighten one of the isofrequency contours, the PC shows an all-angle quasi-self-collimation (quasi-SC) effect. To investigate the straightness of the isofrequency contour and the quasi-SC effect, we propose a straightness factor L based on the method of least squares. With L ≤ L0 (L0 = 0.01 is the critical value), the isofrequency contour is sufficiently straight to induce the quasi-SC effect with the beam quasi-collimating in the structure. Furthermore, the efficiency of light coupling to the quasi-SC PC is studied and can be greatly improved by applying a carefully designed antireflection structure. This quasi-SC effect of the PC and the coupling structure may see applications in novel optical devices and photonic circuits.
Keywords :
elemental semiconductors; integrated optics; laser beams; least squares approximations; optical collimators; optical couplers; optical design techniques; photonic crystals; silicon; all-angle quasiself-collimation effect; antireflection structure design; isofrequency contour straightness; least squares method; light coupling; optical devices; photonic circuits; quasiSC effect; rectangular lattice; rod-type silicon photonic crystal; straightness factor; Couplings; Diffraction; Lattices; Optical devices; Photonic crystals; Photonics; Silicon; Coupling efficiency; antireflection layer; coupling efficiency; photonic crystals; quasi-self-collimation;
Journal_Title :
Photonics Journal, IEEE
DOI :
10.1109/JPHOT.2015.2399433
