Centro de Investigaciones en Láseres y Aplicaciones (CEILAP), Instituto de Investigaciones Científicas y Técnicas para la Defensa (CITEDEF), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), J. B. de La Salle 4397, (1603) Villa Martelli, Argentina.
Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Autónoma de Buenos Aires, Argentina and Université de la Nouvelle Calédonie, ISEA, Boîte Postale R4, Noumea, Nouvelle Calédonie, France.
Phys Rev E. 2018 Mar;97(3-1):032215. doi: 10.1103/PhysRevE.97.032215.
The passively Q-switched, self-pulsing all-solid-state laser is a device of widespread use in many applications. Depending on the condition of saturation of the absorber, which is easy to adjust, different dynamical regimes are observed: continuous-wave emission, stable oscillations, period doubling bifurcations, chaos, and, within some chaotic regimes, extreme events (EEs) in the form of pulses of extraordinary intensity. These pulses are sometimes called "dissipative optical rogue waves." The mechanism of their formation in this laser is unknown. Previous observations suggest they are caused by the interaction of a few transverse modes. Here we report a direct observation of the pulse-to-pulse evolution of the transverse pattern. In the periodical regimes, sequences of intensities are correlated with sequences of patterns. In the chaotic ones, a few different patterns alternate, and the EEs are related with even fewer ones. In addition, the series of patterns and the pulse intensities before and after an EE are markedly repetitive. These observations demonstrate that EEs follow a deterministic evolution, and that they can appear even in a system with few interacting modes. This information plays a crucial role for the development of a mathematical description of EEs in this laser. This would allow managing the formation of EE through control of chaos, which is of both academic and practical interest (laser rangefinder).
被动调 Q、自脉冲全固态激光器是一种在许多应用中广泛使用的设备。根据容易调节的吸收体的饱和条件，可以观察到不同的动力学状态：连续波发射、稳定振荡、倍周期分岔、混沌，以及在某些混沌状态下，以异常强度脉冲形式出现的极端事件 (EE)。这些脉冲有时被称为“耗散光学孤子波”。它们在这种激光器中的形成机制尚不清楚。以前的观察表明，它们是由少数几个横向模式的相互作用引起的。在这里，我们报告了对横向模式脉冲到脉冲演化的直接观察。在周期性状态下，强度序列与模式序列相关。在混沌状态下，少数不同的模式交替出现，而 EE 则与更少的模式相关。此外，在 EE 前后的模式序列和脉冲强度明显具有重复性。这些观察结果表明，EE 遵循确定性演化，即使在只有少数相互作用模式的系统中也会出现 EE。这些信息对于开发这种激光器中 EE 的数学描述起着至关重要的作用。这将允许通过控制混沌来管理 EE 的形成，这既具有学术意义又具有实际意义（激光测距仪）。
