Electron emission from a metallic surface by application of light is known as

Electron emission from a metallic surface by the application of light is known as photoelectric emission [1]. This phenomenon, also called the photoelectric effect, occurs when electromagnetic radiation, such as ultraviolet or visible light, strikes a material and causes the emission of electrons [3]. While the effect can be observed in various materials, it is most readily observable in metals because the incident light ejects electrons from the metallic surface, creating a charge imbalance [4]. In contrast, thermionic emission is driven by thermal energy, and field emission is induced by a strong electric field [2]. Photoelectric emission is a fundamental process in electronic physics and quantum mechanics, where the energy of the incident photons must exceed the material's work function to release electrons [4].

Sources

1. [1] https://www.sciencedirect.com/topics/chemistry/electron-emission
2. [3] https://pmc.ncbi.nlm.nih.gov/articles/PMC12422092/
3. [4] https://www.sciencedirect.com/topics/chemistry/field-emission
4. [2] https://en.wikipedia.org/wiki/Photoelectric_effect