What is quasi-fermi level?

Answer 1

The quasi-Fermi level refers to the energy levels of electrons and holes in a semiconductor that is under non-equilibrium conditions, such as when it is illuminated or biased. Unlike the Fermi level, which represents the energy distribution of particles at equilibrium, quasi-Fermi levels for electrons and holes indicate the separate distributions for each carrier type. This concept is crucial for understanding the behavior of semiconductor devices, particularly in analyzing their performance in photonic and electronic applications. The quasi-Fermi levels help to determine carrier concentrations and recombination rates in these non-equilibrium situations.