Atomic Physics

Atomic physics studies the structure of atoms and the interplay between their components — electrons, protons, and neutrons — as well as how atoms interact with light and other particles.

Structure & energy quantization

An atom consists of a nucleus of protons and neutrons surrounded by a shell of electrons, which can only occupy certain discrete energy levels. When an electron drops to a lower level, the released energy is emitted as light.

Spectral lines

Because these electron transitions are characteristic of each element, every atom has a unique spectrum. This principle is used to identify elements — in astrophysics or analytical chemistry, for example.

Laser theory

Lasers rely on stimulated emission: excited electrons are prompted to drop to a lower energy level, producing coherent light — a direct, practical application of atomic-physics fundamentals.

Quantum mechanics

Because all of this plays out at extremely small scales, it can only be described correctly using the tools of quantum mechanics — including the uncertainty principle and the quantized nature of energy and particles.