Quantum Tunneling Simulator (3D)

The 2D original renders quantum tunneling as an animated barrier diagram driven by four controls — barrier type, barrier height (eV), barrier width (nm), particle energy (eV) and particle mass (in electron masses) — and computes transmission/reflection percentages, a tunneling time, wave vector, de Broglie wavelength and tunneling current from those inputs. This 3D companion keeps the same four physical parameters, but replaces the 2D page's simplified transmission estimate with the exact textbook rectangular-barrier formula: when the particle energy E is below the barrier height V₀, T = 1 / (1 + V₀²·sinh²(κL) / [4E(V₀−E)]) with decay constant κ = √(2m(V₀−E))/ħ; when E exceeds V₀ the particle propagates over the barrier with T = 1 / (1 + V₀²·sin²(k₂L) / [4E(E−V₀)]). Both regimes are computed live from real physical constants (ħ, electron mass, eV, nm) as the sliders move, and a probability-density ribbon — the standing-wave interference of the incident and reflected waves before the barrier, the evanescent (or oscillatory, over-barrier) decay inside it, and the flat transmitted density beyond it — is drawn as genuine 3D geometry you can orbit. A continuous stream of particles is fired at the barrier and each one samples pass/fail from that same computed transmission probability T, so the live measured ratio converges to the theoretical value exactly as it would in a real Monte Carlo tunneling experiment.