electron field emission

Electron field emission is a process where electrons are pulled out of a material's surface when a strong electric field is applied. At the microscopic level, the electric field lowers the energy barrier that keeps electrons bound within the material, allowing them to tunnel through this barrier and escape into the vacuum or space surrounding the material. This phenomenon is utilized in vacuum electronic devices, electron microscopes, and advanced display technologies, enabling electron flow without the need for heating or traditional thermionic emission. Essentially, a powerful enough electric field can directly extract electrons from a solid surface.