Stable oscillations in laser-induced thermal plume/surface interaction in several molecular liquids

Abstract

This study explores the dynamics of thermal plumes induced by laser heating in piperidine, 1-butanol, and 1-pentanoic acid near their liquid/air interfaces. Utilizing a collimated laser beam, cylindrical heated regions are generated, acting as sources for thermal plumes outlined by refractive index gradients due to sharp temperature changes. The interaction between these plumes and the surface introduces unique steady-state dynamics, manifesting as either stable-point dynamics or anharmonic oscillations, depending on the molecular liquid and experimental conditions. Piperidine, 1-butanol, and 1-pentanoic acid each exhibit steady-state oscillation. Methanol and ethylene glycol serve as counterexamples, having stable-point dynamics. The implications of these findings are of relevance for the fields of nonlinear dynamics and dynamical systems, providing experimental examples of limit cycles.