近日，美国加州大学的Chee Wei Wong&Futai Hu及其研究团队取得一项新进展。经过不懈努力，他们揭示了梳孤子晶体的时空呼吸子动力学。相关研究成果已于2024年9月12日在国际知知名学术期刊《光：科学与应用》上发表。

本研究独特地探索并观察了频率微梳中光学孤子晶体的时空呼吸子动力学，通过非线性测量与理论分析，深入研究了空间呼吸子、混沌转换以及动力学确定性切换。为了理解呼吸子孤子，研究人员描述了它们的动力学路径，并展示了两个集合空间呼吸子的过渡图，分别对应有无混沌初始化的情形。

研究人员阐明了孤子晶体微梳中呼吸子动力学的物理机制，包括在相互作用平面上的极限环、以及由三阶色散引起的奇偶对称性破缺所揭示的畴壁理解。

研究人员展示了可访问非线性区域的图谱、呼吸子频率对三阶色散和避免模式交叉强度的依赖性，以及集体呼吸子时空状态之间的转换。该研究的测量范围与基于第一性原理的理论及非线性建模结果高度吻合。

为了成像这些孤子集合及其呼吸子，研究人员进一步构建了全景时间成像系统，实现了对呼吸子同时进行的快慢轴二维映射。

在相位差分采样中，他们展示了孤子晶体呼吸子的二维演化图，包括含有缺陷的稳定呼吸子及漂移呼吸子。这一基础研究有助于理解孤子晶体复合物中的非线性动力学、其时空依赖性以及稳定存在区域。

据悉，孤子，作为非线性和色散之间独特的平衡，为超快电磁脉冲整形、高次谐波产生、实时图像处理以及射频光子通信提供了一条途径。

附：英文原文

Title: Spatio-temporal breather dynamics in microcomb soliton crystals

Author: Hu, Futai, Vinod, Abhinav Kumar, Wang, Wenting, Chin, Hsiao-Hsuan, McMillan, James F., Zhan, Ziyu, Meng, Yuan, Gong, Mali, Wong, Chee Wei

Issue&Volume: 2024-09-12

Abstract: Solitons, the distinct balance between nonlinearity and dispersion, provide a route toward ultrafast electromagnetic pulse shaping, high-harmonic generation, real-time image processing, and RF photonic communications. Here we uniquely explore and observe the spatio-temporal breather dynamics of optical soliton crystals in frequency microcombs, examining spatial breathers, chaos transitions, and dynamical deterministic switching – in nonlinear measurements and theory. To understand the breather solitons, we describe their dynamical routes and two example transitional maps of the ensemble spatial breathers, with and without chaos initiation. We elucidate the physical mechanisms of the breather dynamics in the soliton crystal microcombs, in the interaction plane limit cycles and in the domain-wall understanding with parity symmetry breaking from third-order dispersion. We present maps of the accessible nonlinear regions, the breather frequency dependences on third-order dispersion and avoided-mode crossing strengths, and the transition between the collective breather spatio-temporal states. Our range of measurements matches well with our first-principles theory and nonlinear modeling. To image these soliton ensembles and their breathers, we further constructed panoramic temporal imaging for simultaneous fast- and slow-axis two-dimensional mapping of the breathers. In the phase-differential sampling, we present two-dimensional evolution maps of soliton crystal breathers, including with defects, in both stable breathers and breathers with drift. Our fundamental studies contribute to the understanding of nonlinear dynamics in soliton crystal complexes, their spatio-temporal dependences, and their stability-existence zones.

DOI: 10.1038/s41377-024-01573-4

Source: https://www.nature.com/articles/s41377-024-01573-4