Observation of Floquet solitons in a topological bandgap
Observation of Floquet solitons in a topological bandgap
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DOI：
10.1126/science.aba8725
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发表时间：
2020-05-22
期刊：
影响因子：
56.9
通讯作者：
Rechtsman, Mikael C.
中科院分区：
文献类型：
--
作者：
Mukherjee, Sebabrata;Rechtsman, Mikael C.
拓扑保护是一种普遍现象，适用于电子，光子，超冷原子，机械和其他系统。这些系统中的绝大多数研究都探索了线性域，其中粒子间的相互作用可以忽略不计。我们在实验上观察到孤子-传播而不改变形状的非线性的结果-在光子Floquet拓扑绝缘体。这些孤子表现出独特的行为，因为它们执行与底层拓扑结构相关的回旋加速器样轨道。具体地说，我们使用了波导阵列与周期性变化沿着波导轴，从而引起非零绕组数，和非线性引起的光学克尔效应。这一结果适用于一系列玻色子系统，因为它是由聚焦非线性薛定谔方程（等效地，吸引力Gross-Pitaevskii方程）描述的。
Topological protection is a universal phenomenon that applies to electronic, photonic, ultracold atomic, mechanical, and other systems. The vast majority of research in these systems has explored the linear domain, where interparticle interactions are negligible. We experimentally observed solitons-waves that propagate without changing shape as a result of nonlinearity-in a photonic Floquet topological insulator. These solitons exhibited distinct behavior in that they executed cyclotron-like orbits associated with the underlying topology. Specifically, we used a waveguide array with periodic variations along the waveguide axis, giving rise to nonzero winding number, and the nonlinearity arose from the optical Kerr effect. This result applies to a range of bosonic systems because it is described by the focusing nonlinear Schrodinger equation (equivalently, the attractive Gross-Pitaevskii equation).