Gain characteristics of ideal dilute nitride quantum well lasers

We use a realistic Hamiltonian to compare the gain characteristics of an ideal InGaAsN/GaAs quantum well laser structure emitting at View the MathML source with an equivalent N-free InGaAs/GaAs structure. The energy gap of InGaAs is reduced by the addition of N, due to a repulsive interaction between an N resonant band and the conduction band edge. This interaction increases the conduction band edge effective mass and decreases the value of the dipole matrix element linking the conduction and valence band edges. We find that the addition of N reduces the peak gain and differential gain at fixed carrier density, although the gain saturation value and the peak gain as a function of radiative current density are largely unchanged due to the incorporation of N.