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arXiv · 2311.14504

Ultra-slow dynamics of free-running ring lasers: towards a minimal model

Giovanni Giacomelli·Antonio Politi
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Abstract

The dynamics of a resonant, free-running ring laser, in the common case of a fast relaxation of the atomic polarization, is unexpectedly highly singular. As shown in [Phys. Rev. Research, {\bf 5}, 023059 (2023)], this is due to the closeness to a pure Hamiltonian dynamics ruled by a nonlinear wave equation, herein named Klein-Gordon-Toda model. In this paper, we derive a quasi-Hamiltonian model which allows describing realistic systems. In particular, we identify two nearly conserved, energy-like quantities, which ``naturally" exhibit an ultra-slow dynamics confirmed and highlighted by numerical simulations. A minimal version of the quasi-Hamiltonian model is finally derived, which does not only reproduce the laser thresholds, but also helps understanding the origin of the nearly integrable character of the laser dynamics.

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Giovanni Giacomelli, Antonio Politi. 2023-11-24. Ultra-slow dynamics of free-running ring lasers: towards a minimal model. https://arxiv.org/abs/2311.14504

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