Related Experiment Video
Updated: Jul 16, 2026

Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
Conical diffraction and gap solitons in honeycomb photonic lattices
Or Peleg1, Guy Bartal, Barak Freedman
1Department of Physics and Solid State Institute, Technion, Haifa 32000, Israel.
Abstract:
We study wave dynamics in honeycomb photonic lattices, and demonstrate the unique phenomenon of conical diffraction around the singular diabolical (zero-effective-mass) points connecting the first and second bands. This constitutes the prediction and first experimental observation of conical diffraction arising solely from a periodic potential. It is also the first study on k space singularities in photonic lattices. In addition, we demonstrate "honeycomb gap solitons" residing in the gap between the second and the third bands, reflecting the special properties of these lattices.
Related Concept Videos
Interference and Diffraction
Standing Waves in a Cavity
X-ray Crystallography
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
The de Broglie Wavelength
Structures of Solids
Imperfections in Crystal Structure: Stoichiometric Point Defects

