Quantum Tunnelling: A Journey Through the Microscopic Realm

What Quantum Tunnelling Is

Quantum tunnelling is a phenomenon where particles can pass through potential barriers even if they do not have enough energy to classically overcome them. This effect arises from the wave-like nature of quantum particles and their associated probability amplitudes.

The concept was first introduced by Gurney and Condon in 1928, but it wasn't until later that its significance for technology was fully appreciated.

How Quantum Tunnelling Works

When a particle encounters a potential barrier, the wavefunction of the particle extends into the region where classically it would be forbidden. If the probability amplitude in this region is non-zero, there's a chance that the particle can tunnel through the barrier and emerge on the other side with a certain probability.

This phenomenon is governed by the Schrödinger equation, which describes how the wavefunction of a quantum system evolves over time.

Why It Matters

Quantum tunnelling has numerous applications in modern technology. For instance, it underpins the operation of scanning tunneling microscopes and is crucial for semiconductor devices like transistors.

Understanding quantum tunnelling also helps in developing new materials with novel properties, such as superconductors and quantum dots.

Real-World Examples

One of the most famous applications is in tunnel diodes, which are used to amplify signals and generate oscillations. Another example is in nuclear fusion processes, where particles can overcome the Coulomb barrier through tunnelling.

In the realm of electronics, quantum tunnelling is essential for the operation of flash memory devices, enabling rapid data storage and retrieval.

Frequently asked questions

Try it live

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