Chaos and extreme events in a geometric-ring-mode laser

Abstract

We generated the geometric-ring-mode by a four-element Nd:YVO4 laser There were two modes corresponding to the clockwise mode and the counterclockwise mode respectively First we observed the characteristic of power pattern and divergence angles by gradually shortening cavity length Second we measured the relaxation oscillation frequency observing the variance of value from Gaussian mode to the geometric-ring-mode Then we studied the nonlinear dynamics by pump modulation When the modulation frequency was operated near the relaxation oscillation frequency the period-doubling route to chaos was observed while increasing the modulation depth Simultaneously extreme events were observed right after chaos regime Moreover we observed obvious mode competition between two modes Thus we analyzed the noise caused by fluctuations and then we calculated probabilities of the extreme events occurrence Finally we found a high correlation between extreme events and noise

Date of Award	2019
Original language	English
Supervisor	Ming-Dar Wei (Supervisor)