Dependence of the volume of eigenmodes of a one-dimensional random laser on the inverse population of the active medium

A one-dimensional random laser consisting of a disordered system of layers with different permittivity values, some of which contain an active medium, has been considered. Such a system has been modeled as a chain of Fabry–Perot cavities separated by nonresonant layer subsystems. It has been assumed that light passing through such subsystems is weakened. The properties of partial eigenmodes of such cavities with increasing pump power of the active medium have been studied. It has been shown that the pulling of the mode frequencies that occurs with increasing pump power causes the formation of coupled cavity chains and an increase in the average volume of partial eigenmodes.