Crescent shaped dielectric periodic structure for light manipulation

Kurt H., Turduev M., Giden I.

Optics Express, vol.20, no.7, pp.7184-7194, 2012 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 20 Issue: 7
  • Publication Date: 2012
  • Doi Number: 10.1364/oe.20.007184
  • Journal Name: Optics Express
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.7184-7194
  • TED University Affiliated: No


We present optical properties of crescent-shaped dielectric nanorods that comprise a square lattice periodic structure named as crescentshaped photonic crystals (CPC). The circular symmetry of individual cells of periodic dielectric structures is broken by replacing each unit cell with a reduced symmetry crescent shaped structure. The created configuration is assumed to be formed by the intersection of circular dielectric and air rods. The degree of freedom to manipulate the light propagation arises due to the rotational sensitivity of the CPC. The interesting dispersion property of designed CPC occurs due to the anisotropic nature of the iso-frequency contours that yield tilted self-collimated wave guiding. Furthermore, this feature allows focusing, routing, splitting and deflecting light beams along certain routes which are independent of the lattice symmetry directions of regular PCs. The propagation direction of light can be tuned by means of the opening angle of the crescent shape. Finally, the property of being alldielectric structure ensures the absence of optical absorption losses that are reminiscent of employed metallic nano-particles. © 2012 Optical Society of America.