How is a regular semiconductor laser built?
Researchers can harness electron movement to produce a laser. In a free-floating atom, electrons orbit in rings closer to or farther from the nucleus, depending on how much energy the electron is carrying. In a solid, atoms are fixed in a lattice (like a complex chain or pattern), and electrons move in and jump between energy bands instead of between the fixed energy levels corresponding to the various orbits in free atoms. In semiconducting materials, electrons can move into an energy band, called a conduction band, which produces a current. They can also move inside a band called a valence band that is so jam-packed with electrons that no net current flow happens. Electrons can easily be stimulated to move to the conduction bandbut to maintain equilibrium, they eventually have to return to the valence band to fill in the “holes”. they left behind. The electron returns to the valence band via a port or “well” in the conduction band, which dips closer to the valence band in a region ca
