No higher resolution available.
Bragg_Diffraction.gif (480 × 480 pixels, file size: 13.34 MB, MIME type: image/gif, looped, 120 frames, 12 s)
 | This is a file from the Wikimedia Commons. Information from its description page there is shown below. Commons is a freely licensed media file repository. You can help. |
Summary
| Description |
English: A line of point scatterers behave approximately as a partial mirror. When the scatterers are arranged in a crystal, each line will reflect light, and all of those reflections will interfere with each other.
(Animation made for scalar fields in 2D) |
| Date | |
| Source | https://twitter.com/j_bertolotti/status/1261314633673080835 |
| Author | Jacopo Bertolotti |
| Permission (Reusing this file) |
https://twitter.com/j_bertolotti/status/1030470604418428929 |
Mathematica 12.0 code
sinstep[t_] := Sin[\[Pi]/2 t]^2
stopstep[t_] := t (2 - t);
\[Lambda] = Sqrt[2];
k0 = (2 \[Pi])/\[Lambda];
c = 1;
\[Omega] = c k0;
\[Alpha] = 4/(k0^2 I);
\[Sigma] = (k0^3 Norm[\[Alpha]]^2)/4;
G[r_] := N[I/4 HankelH1[0, k0 Norm[r] ]];
ReMapC[x_] := RGBColor[(Cos[2 \[Pi] x] + 1)/2 UnitStep[x - 0.5], 0, (Cos[2 \[Pi] x] + 1)/2 UnitStep[0.5 - x]];
\[Theta] = -\[Pi]/4;
E0[x_, y_] := E^(I k0 (Cos[\[Theta]] x + Sin[\[Theta]] y))/4 E^(-((-Sin[\[Theta]] x + Cos[\[Theta]] y)^2/(2 3^2)));
p0 = Table[
sources = {stopstep[t] ({-5, 0} - {11, 0}) + {11, 0}};
nsources = Dimensions[sources][[1]];
DensityPlot[
Re[E0[x, y]/4 + Sum[G[{x, y} - sources[[j]]] E0[sources[[j, 1]], sources[[j, 2]] ], {j, 1, nsources}] ], {x, -10, 10}, {y, -10, 10}, PlotPoints -> 100, ColorFunction -> ReMapC, Frame -> False, PlotRange -> {-0.5, 0.5}, RegionFunction -> Function[{x, y}, And @@ Table[Norm[{x, y} - sources[[j]]] > 0.2, {j, 1, nsources}] ], Epilog -> { Black, Thick, Table[Circle[sources[[j]], 0.2], {j, 1, nsources}]}]
, {t, 0, 1, 0.05}];
p1 = Table[
sources = Table[{j, 0}, {j, -5, k, 1}];
nsources = Dimensions[sources][[1]];
DensityPlot[
Re[E0[x, y]/10 + Sum[G[{x, y} - sources[[j]]] E0[sources[[j, 1]], sources[[j, 2]] ], {j, 1, nsources}] ], {x, -10, 10}, {y, -10, 10}, PlotPoints -> 100, ColorFunction -> ReMapC, Frame -> False, PlotRange -> {-0.5, 0.5}, RegionFunction -> Function[{x, y}, And @@ Table[Norm[{x, y} - sources[[j]]] > 0.2, {j, 1, nsources}] ], Epilog -> {White, Table[Disk[sources[[j]], 0.2], {j, 1, nsources}], Black, Thick,
Table[Circle[sources[[j]], 0.2], {j, 1, nsources}]}]
, {k, -4, 5, 1}];
p2 = Table[
sources =
sinstep[t]*(Table[{j, j - 5}, {j, -5, 5, 1}] - Table[{j, 0}, {j, -5, 5, 1}]) + Table[{j, 0}, {j, -5, 5, 1}];
nsources = Dimensions[sources][[1]];
DensityPlot[
Re[E0[x, y]/10 + Sum[G[{x, y} - sources[[j]]] E0[sources[[j, 1]], sources[[j, 2]] ], {j, 1, nsources}] ], {x, -10, 10}, {y, -10, 10}, PlotPoints -> 100, ColorFunction -> ReMapC, Frame -> False, PlotRange -> {-0.5, 0.5}, RegionFunction -> Function[{x, y}, And @@ Table[ Norm[{x, y} - sources[[j]]] > 0.2, {j, 1, nsources}] ], Epilog -> {White, Table[Disk[sources[[j]], 0.2], {j, 1, nsources}], Black, Thick,
Table[Circle[sources[[j]], 0.2], {j, 1, nsources}]}]
, {t, 0, 1, 0.051}];
p3 = Table[
sources = Flatten[Table[{x, y} , {x, -5, 5, 1}, {y, 0, -k, -1}], 1];
nsources = Dimensions[sources][[1]];
DensityPlot[
Re[E0[x, y]/10 + Sum[G[{x, y} - sources[[j]]] E0[sources[[j, 1]], sources[[j, 2]] ], {j, 1, nsources}] ], {x, -10, 10}, {y, -10, 10}, PlotPoints -> 100, ColorFunction -> ReMapC, Frame -> False, PlotRange -> {-0.5, 0.5}, RegionFunction -> Function[{x, y}, And @@ Table[Norm[{x, y} - sources[[j]]] > 0.2, {j, 1, nsources}] ], Epilog -> {White, Table[Disk[sources[[j]], 0.2], {j, 1, nsources}], Black, Thick,
Table[Circle[sources[[j]], 0.2], {j, 1, nsources}]}]
, {k, 0, 3, 1}];
ListAnimate[Join[p0, p1, p2, Reverse[p2], p3, Table[p3[[-1]], {10}] , Reverse[p3], Reverse[p1], Reverse[p0] ] ]
Licensing
I, the copyright holder of this work, hereby publish it under the following license:
 
|
This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication. |
| The person who associated a work with this deed has dedicated the work to the public domain by waiving all of their rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law. You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission.
|
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 11:37, 16 May 2020 | | 480 × 480 (13.34 MB) | Berto | Uploaded own work with UploadWizard |
File usage
The following pages on the English Wikipedia use this file (pages on other projects are not listed):
