Molecular Beam Epitaxy Growth Simulator

Molecular beam epitaxy grows crystalline films one atom at a time, and whether the result is atomically smooth or hopelessly rough comes down to a race between deposition and diffusion. This simulator fires a real particle beam onto a substrate grid, lets each adatom either stick where it lands or hop toward the nearest low point depending on the temperature-controlled diffusion length, and tracks the resulting height map's roughness in real time. Watch the simulated RHEED specular intensity oscillate once per completed monolayer at high temperature — the same signal MBE labs use to count atomic layers as they grow — and collapse into noise when the flux is too high or the substrate too cold for adatoms to find a step edge before they're buried.