Super-quadratic scaling anomaly in excitation power dependence of photoluminescence: Optically detected quasi-Fermi edge resonance

Abstract

Standard model of electron–hole recombination predicts a sub-quadratic scaling of photoluminescence intensity as a function of the excitation power, which often helps clarify the underlying physical processes. This cardinal rule is defied in a system with discontinuous density-of-states (DOS). An anomalous super-quadraticity is observed in a superlattice-clad quantum well as quasi-Fermi edge crosses the DOS discontinuity. A DOS-dependent exponent, m(DOS), accounts for an unprecedented optically detected Fermi edge resonance that is observed.