IV. Physical Institute-Solids and Nanostructures, University of Göttingen, Göttingen, Germany.
Department of Electrical Engineering, University of California, Los Angeles, CA, USA.
Science. 2017 Apr 7;356(6333):50-54. doi: 10.1126/science.aal5326.
Solitons, particle-like excitations ubiquitous in many fields of physics, have been shown to exhibit bound states akin to molecules. The formation of such temporal soliton bound states and their internal dynamics have escaped direct experimental observation. By means of an emerging time-stretch technique, we resolve the evolution of femtosecond soliton molecules in the cavity of a few-cycle mode-locked laser. We track two- and three-soliton bound states over hundreds of thousands of consecutive cavity roundtrips, identifying fixed points and periodic and aperiodic molecular orbits. A class of trajectories acquires a path-dependent geometrical phase, implying that its dynamics may be topologically protected. These findings highlight the importance of real-time detection in resolving interactions in complex nonlinear systems, including the dynamics of soliton bound states, breathers, and rogue waves.
孤子，这种在物理学许多领域普遍存在的类粒子激发，已被证明具有类似于分子的束缚态。这种时间孤子束缚态的形成及其内部动力学一直无法通过直接实验观察到。通过新兴的时间拉伸技术，我们解决了在几周期锁模激光腔中的飞秒孤子分子的演化。我们在数十万次连续腔循环中跟踪双孤子和三孤子束缚态，确定了固定点和周期性和非周期性分子轨道。一类轨迹获得了与路径相关的几何相位，这意味着其动力学可能受到拓扑保护。这些发现强调了实时检测在解决复杂非线性系统中相互作用的重要性，包括孤子束缚态、呼吸子和不规则波的动力学。
