Optical gain

Optical gain refers to the process by which a material amplifies light signals passing through it. When energy is supplied to such a material—such as by electrical current—more atoms or molecules are energized into a state called "excited." As these excited particles return to their normal state, they release additional photons, or light particles, that match the original light's properties. This results in an increase in the intensity of the light, effectively amplifying the signal. Optical gain is fundamental in devices like lasers and optical amplifiers, enabling efficient transmission and manipulation of light-based information.