Tuning random lasing in photonic glasses

TL;DR

This paper numerically investigates how to tune the wavelength of a diffusive random laser in photonic glasses by exciting Mie resonances, revealing complex mode competition effects on lasing thresholds.

Contribution

It introduces a comprehensive numerical model that accounts for dispersion and mode competition, advancing understanding of tunability in random lasers made of latex spheres and rhodamine.

Findings

Lasing wavelength tunability range quantified.

Threshold behavior influenced by mode competition, not just wavelength.

Realistic modeling of photonic glasses with dispersion effects.

Abstract

We present a detailed numerical investigation of the tunability of a diffusive random laser when Mie resonances are excited. We solve a multimode diffusion model and calculate multiple light scattering in presence of optical gain which includes dispersion in both scattering and gain, without any assumptions about the $\beta$ parameter. This allows us to investigate a realistic photonic glass made of latex spheres and rhodamine and to quantify both the lasing wavelength tunability range and the lasing threshold. Beyond what is expected by diffusive monochromatic models, the highest threshold is found when the competition between the lasing modes is strongest and not when the lasing wavelength is furthest from the maximum of the gain curve.