What Is Quantum Efficiency?

Quantum efficiency is an important parameter describing the photoelectric conversion capability of optoelectronic devices. It is the ratio of the average number of photoelectrons to the number of incident photons per unit time at a specific wavelength. ^{[1] According to} the surface state (rough surface or smooth surface) of the photoelectric surface, the amount of photoelectron emission also changes. However, due to reflection and other reasons, there are generally fewer electrons that escape from photon energy. In most cases, it is about 1% to 25%. ^[2]

Quantum efficiency is an accurate measurement of a device's sensitivity to light. Since the energy of the photon is the inverse of the wavelength

Quantum efficiency (QE), or spectral response, or photoelectric conversion efficiency (IPCE), is broadly defined as the value of the photovoltaic characteristics of a solar cell under different wavelengths of light. The quantum efficiency QE and the photoelectric conversion efficiency IPCE both refer to the ratio of the number of electron-hole pairs generated by a solar cell to the number of photons incident on the surface of the solar cell. Generally, the solar cell quantum efficiency QE refers to the external quantum efficiency EQE, which means that the photon reflection loss on the surface of the solar cell is not considered. ^[7]