Chaos in the pulse spacing of passive Q - switched all- solid state lasers

MARCELO KOVALSKY; ALEJANDRO HNILO.

OPTICS LETTERS

OPTICAL SOC AMER

Año: 2010 vol. 30 p. 3498 - 3500

0146-9592

We report the experimental and theoretical verification that, in a diode-pumped Nd:YAG þ Cr:YAG Q-switched laser,the instabilities in the pulse spacing (?jitter?) are ruled by low-dimensional deterministic chaos. From our experimentaltime series, we determine the embedding and fractal dimensions of the attractor, as well as the values of theLyapunov exponents. We also present a simplified theoretical description in terms of a map of the same universalityclass as the logistic map, which explains the bifurcations? cascade and the period-three window of stability observed.The achieved characterization of the dynamics and its main parameters opens a door to effective waysto reduce the jitter, which is of practical interest, through mechanisms of control of chaos. Conversely, the difficultyin the prediction of the interpulse spacing makes this system attractive for high power, robust FM chaotic lasercryptography in free-space propagation. We report the experimental and theoretical verification that, in a diode-pumped Nd:YAG þ Cr:YAG Q-switched laser,the instabilities in the pulse spacing (?jitter?) are ruled by low-dimensional deterministic chaos. From our experimentaltime series, we determine the embedding and fractal dimensions of the attractor, as well as the values of theLyapunov exponents. We also present a simplified theoretical description in terms of a map of the same universalityclass as the logistic map, which explains the bifurcations? cascade and the period-three window of stability observed.The achieved characterization of the dynamics and its main parameters opens a door to effective waysto reduce the jitter, which is of practical interest, through mechanisms of control of chaos. Conversely, the difficultyin the prediction of the interpulse spacing makes this system attractive for high power, robust FM chaotic lasercryptography in free-space propagation. We report the experimental and theoretical verification that, in a diode-pumped Nd:YAG þ Cr:YAG Q-switched laser,the instabilities in the pulse spacing (?jitter?) are ruled by low-dimensional deterministic chaos. From our experimentaltime series, we determine the embedding and fractal dimensions of the attractor, as well as the values of theLyapunov exponents. We also present a simplified theoretical description in terms of a map of the same universalityclass as the logistic map, which explains the bifurcations? cascade and the period-three window of stability observed.The achieved characterization of the dynamics and its main parameters opens a door to effective waysto reduce the jitter, which is of practical interest, through mechanisms of control of chaos. Conversely, the difficultyin the prediction of the interpulse spacing makes this system attractive for high power, robust FM chaotic lasercryptography in free-space propagation.