Quantum
Quantum Tunneling Lab
Even when a particle has less energy than a barrier, quantum mechanics leaves a finite chance of transmission. This lab uses dimensionless units to show how energy, width, and barrier height shape that probability.
What the picture means
The cyan line tracks the wave amplitude. When energy is below the barrier, the wave decays inside the barrier but does not vanish completely, so a smaller transmitted wave still emerges on the far side.