electronhole

An electronhole, more commonly referred to simply as a hole, is a concept in solid-state physics describing the absence of an electron in a filled valence band of a crystal. When electrons are excited out of the valence band—by thermal energy or photon absorption—holes are created alongside electrons in the conduction band. Holes behave as positively charged quasiparticles with their own mobility and effective mass, which depend on the material’s band structure.

Holes move through a crystal as electrons jump to fill the vacancy, making the absence appear to move in the opposite direction. This motion gives rise to hole currents in electrical circuits. In many semiconductors, holes are the majority charge carriers in p-type materials, formed by acceptor dopants, while electrons are the majority carriers in n-type materials. Holes also exist as minority carriers in regions where electrons dominate.

A key process involving holes is recombination, where a free electron recombines with a hole, releasing energy as heat or photons. Recombination competes with generation and diffusion of carriers, influencing device behavior.

In devices, holes play essential roles alongside electrons. In pn junctions, diodes, and transistors, the manipulation of hole transport enables rectification and amplification. In solar cells, the separation and collection of photo-generated electron-hole pairs generate electric power. Although holes are often treated as positive charges, they are not physical particles; rather, they are emergent quasiparticles that provide a convenient framework for describing the collective behavior of many interacting electrons in a solid.