Threshold Behavior of Convective Flows at Thermal Lens Oscillations

Features of accumulate-and-fire system are demonstrated experimentally at excitation of the laser-induced thermal lens oscillations near a fluid interface. The interface ability to retard convective flows is treated as a possible reason for the accumulate-and-fire behavior. Some experimental data become more understandable with this approach. The threshold for the convective flows switching near the fluid interface has another origin in comparison with well-known classic convective thresholds. Association of this phenomenon with the Rayleigh–Taylor instability is discussed.