fotokonduktivitetsmätningar

Fotokonduktivi is a term derived from Greek words meaning "light" and "conductivity." It refers to a phenomenon where a material's electrical conductivity increases when it is exposed to electromagnetic radiation, such as light. This property is known as photoconductivity.

The underlying mechanism involves the absorption of photons by the material. When a photon with sufficient energy strikes the material, it can excite an electron from its bound state to a more mobile state, such as the conduction band. This excitation creates an electron-hole pair, where the electron is a free charge carrier and the "hole" acts as a positive charge carrier. The increased number of free charge carriers in the material leads to a measurable increase in its electrical conductivity.

The extent of photoconductivity depends on several factors, including the material's properties, the wavelength and intensity of the incident radiation, and the temperature. Different materials exhibit photoconductivity at different wavelengths. For example, semiconductors are commonly known for their photoconductive properties and are used in various light-sensitive electronic devices.

Applications of photoconductivity are widespread. Photoconductive materials are fundamental components in devices like solar cells, which convert light energy into electrical energy. They are also used in light sensors, photodetectors, and image sensors found in cameras and scanners. The ability of these materials to change their conductivity in response to light makes them invaluable for sensing and energy conversion technologies.