Quantum Tunneling: A Particle's Path Through Potential

What Quantum Tunneling Is

Quantum tunneling is a phenomenon where particles can pass through potential barriers that they classically shouldn't be able to. This occurs due to the wave-like nature of particles, described by quantum mechanics.

In this simulation, you see a Gaussian wave packet evolving according to the time-dependent Schrodinger equation in one dimension, interacting with a rectangular potential barrier.

How It Works

The wave packet's evolution is governed by the Schrodinger equation, which predicts both the probability distribution of the particle’s position and its momentum. The potential barrier causes the wave function to split into reflected and transmitted parts.

By adjusting parameters like the barrier height and width, as well as the packet energy and width, you can observe how these factors influence the tunneling probability.

Why It Matters

Quantum tunneling is crucial in many technologies, from scanning tunneling microscopes to semiconductor devices. Understanding it helps explain phenomena like alpha decay and electron transport in nanoscale structures.

In the simulation, you can observe how changing parameters affects the transmission and reflection probabilities, which are key to understanding quantum behavior.

Real-World Examples

Quantum tunneling is used in scanning tunneling microscopy (STM), where a sharp tip scans over a surface, detecting electrons that tunnel through the air gap between the tip and sample. This allows imaging of surfaces at atomic resolution.

In semiconductor devices like diodes and transistors, quantum tunneling can lead to leakage currents, which is why it's important for engineers to understand and control.

Frequently asked questions

Try it live

Everything above runs in your browser — open Quantum Tunneling Particles (2D) and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.