Spacing statistics in two-mode random lasing

TL;DR

This paper investigates the spacing statistics of lasing frequencies in two-mode random lasers, revealing mode repulsion and conditions under which the distribution aligns with the Wigner surmise, using non-Hermitian random matrix models.

Contribution

It introduces a spectral analysis of two-mode random lasers using non-Hermitian random matrices, highlighting the dependence of spacing distribution on gain-profile width and mode competition.

Findings

Spacing distribution depends on gain-profile width and mode spacing

Mode repulsion observed in the frequency spacings

Distribution can match the Wigner surmise under certain conditions

Abstract

The distribution of spacings between the lasing frequencies for an ensemble of random lasers in the two-mode regime was computed. The random lasers are implemented as open chaotic cavities filled with an active medium. The spectral properties of the passive cavities are modeled with non-Hermitian random matrices. The spacing distribution is found to depend on the relation between the gain-profile width and the mean spacing of the passive-cavity modes. The distribution displays mode repulsion and, under certain conditions, agrees with the Wigner surmise. The role of mode competition is discussed.