Quantum Yield

Quantum yield is a measure of efficiency in a photophysical or photochemical process. It indicates the ratio of the number of molecules that successfully undergo a specific event—such as emitting light (fluorescence) or reacting chemically—to the total number of molecules that absorb photons (light particles). For example, a quantum yield of 80% means that 8 out of 10 absorbed photons result in the desired outcome. It’s a way to quantify how effectively absorbed light is converted into a meaningful response, helping scientists evaluate and compare the performance of materials like dyes, proteins, or sensors.