fotóelektros

Fotóelektros is a term that can refer to several related phenomena in physics, most commonly the photoelectric effect. The photoelectric effect is the emission of electrons from a material when light shines on it. This effect is a cornerstone of quantum mechanics and was famously explained by Albert Einstein in 1905, earning him the Nobel Prize in Physics.

The energy of the incident light is absorbed by electrons in the material. If this energy is sufficient to overcome the work function of the material (the minimum energy required to remove an electron), the electron will be emitted. The intensity of the light determines the number of electrons emitted, while the frequency of the light determines the kinetic energy of the emitted electrons.

A related concept is the photovoltaic effect, which is the creation of voltage or electric current in a material upon exposure to light. This is the principle behind solar cells, where light energy is converted directly into electrical energy. Photovoltaic devices are made from semiconductor materials that exhibit this effect.

In some contexts, particularly in older or less common usage, "fotóelektros" might also refer to devices that utilize these effects, such as photomultipliers or photodetectors, which are used to detect light and convert it into an electrical signal. The fundamental principle behind these devices is the interaction of light with matter, leading to an electrical response.