Statistical physical theory of mode-locking laser generation with a frequency comb

TL;DR

This paper models mode-locking laser generation using a statistical physics approach, revealing phase transition behavior, power condensation phenomena, and novel properties of the laser phase through Monte Carlo simulations.

Contribution

It introduces a Hamiltonian-based statistical mechanical framework to analyze mode-locking lasers, uncovering phase transition and power condensation phenomena not seen in previous mean-field models.

Findings

Power condensation occurs with strong mode interaction dilution.

Laser threshold and spectra are computed for various conditions.

Novel properties of the mode-locking phase are identified.

Abstract

A study of the Mode-locking lasing pulse formation in closed cavities is presented within a statistical mechanical framework where the onset of laser coincides with a thermodynamic phase transition driven by the optical power pumped into the system. Electromagnetic modes are represented by classical degrees of freedom of a Hamiltonian model at equilibrium in an effective ensemble corresponding to the stationary laser regime. By means of optimized Monte Carlo numerical simulations, the system properties are analyzed varying mode interaction dilution, gain profile and number of modes. Novel properties of the resulting mode-locking laser phase are presented, not observable by previous mean-field approaches. For strong dilution of the nonlinear interaction network, power condensation occurs as the whole optical intensity is taken by a few electromagnetic modes, whose number does not depend on the size of the system. For all reported cases laser thresholds, intensity spectra, and ultra-fast electromagnetic pulses are computed.