Bragg diffraction on a denser lattice

Описание: This is a variant of the recent video    • Bragg diffraction   showing Bragg diffraction on a denser lattice: instead of 40 columns of 8 scatterers, the lattice used here has 60 columns. The changes the direction in which the incoming wave is mainly reflected/
Bragg diffraction (see for instance https://en.wikipedia.org/wiki/Bragg%2... ) occurs when a wave encounters a regular lattice, for instance a crystalline solid. Depending on the wave length, the angle of incidence of the wave, and the geometry of the lattice, interference of the reflected waves can create various patterns, that sometimes allow to deduce properties of the lattice.
The video has two parts, showing the same simulation with two different color schemes:
Wave height: 0:00
Average energy (log scale): 2:09
In the first part, the color hue shows the wave height. In the second part, it shows the energy, averaged from the beginning of the simulation, on a logarithmic scale. There are oscillating boundary conditions on the left side of the simulation, and absorbing boundary conditions on the other sides.

Render time: 38 minutes 6 seconds
Color scheme: Part 1 - Twilight by Bastian Bechtold
https://github.com/bastibe/twilight
Part 2 - Inferno by Nathaniel J. Smith and Stefan van der Walt
https://github.com/BIDS/colormap

Music: "Reconciliation" by Asher Fulero‪@AsherFulero‬

See also https://images.math.cnrs.fr/Des-ondes... for more explanations (in French) on a few previous simulations of wave equations.

The simulation solves the wave equation by discretization. The algorithm is adapted from the paper https://hplgit.github.io/fdm-book/doc...
C code: https://github.com/nilsberglund-orlea...
https://www.idpoisson.fr/berglund/sof...
Many thanks to Marco Mancini and Julian Kauth for helping me to accelerate my code!

#wave_equation #waves #diffraction #Bragg_diffraction