Related Experiment Video
Updated: Jun 29, 2025
Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
Band separation and electric field prediction in square Bravais-Moiré photonic crystals
J Bareño-Silva1, Á H Bedoya-Calle2, H A Gómez-Urrea2
1Doctorate in Modeling and Scientific Computing, Faculty of Basic Sciences, University of Medellin, Cra. 87 # 30-65, Medellin, 050026, Antioquia, Colombia.
Abstract:
In this study, we address three key challenges in photonic crystals: modeling of isolated flat bands, electric field prediction, and band separation in dispersion relations. Using twisted square Bravais lattices at specific angles, we create Bravais-Moiré photonic crystals exhibiting unique characteristics. These include band pairing and parallelism in certain Brillouin zones, enabling predictable electric field behavior and identification of isolated, flat band pairs within extensive band gaps. We apply advanced Shape theory-based classification methods for precise band separation, offering significant contributions to photonics research and light manipulation applications.
Related Concept Videos
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
02:18X-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...
01:27Electrostatic Boundary Conditions in Dielectrics
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's...
01:16Electric Field of Parallel Conducting Plates
Consider a cross-section of a thin, infinite conducting plate having a positive charge. For such a large thin plate, as the thickness of the plate tends to zero, the positive charges lie on the plate's two large faces. Without an external electric...
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
01:30Electric Field of Two Equal and Opposite Charges
A separation of the positive and negative charges can lead to a weak, remnant effect of the positive and negative charges. The expectation is that the more the distance between the positive and...