Spectro-temporal behavior of dye-based solid-state random lasers under picosecond pumping regime: part II

Area of Science:

• Condensed Matter Physics
• Laser Physics
• Photonics

Background:

• Recent investigations explored random laser emission from solid-state dye-doped powders.
• Picosecond pumping revealed intense peaks and spectro-temporal widths near the theoretical limit (ΔωΔt≅1).
• This phenomenon occurred even below the lasing threshold.

Purpose of the Study:

• To propose a simple model explaining the observed emission characteristics.
• To ensure the model aligns with the material's energetic properties.
• To investigate sub-threshold emission decay and the role of scattering.

Main Methods:

• Development of a theoretical model for random laser emission.
• Analysis of photon path lengths and stimulated emission.
• Comparison of model predictions with experimental measurements.
• Evaluation of emission decay in sub-threshold conditions.

Main Results:

• The model successfully explains the spectro-temporal properties of random laser emission.
• Predicted sub-threshold emission decay shows excellent agreement with experimental data.
• Scattering's decisive effect on emission decay was highlighted.
• The results are inconsistent with a conventional mode structure.

Conclusions:

• The proposed model provides a robust explanation for random laser emission characteristics.
• Scattering plays a crucial role in the dynamics of random lasers.
• The findings challenge the applicability of mode-based descriptions for these systems.