振荡波导阵列中孤子的实验发现  

Observation of π solitons in oscillating waveguide arrays

作　　者：Antonina A.Arkhipova Yiqi Zhang Yaroslav V.Kartashov Sergei A.Zhuravitskii Nikolay N.Skryabin Ivan V.Dyakonov Alexander A.Kalinkin Sergei P.Kulik Victor O.Kompanets Sergey V.Chekalin Victor N.Zadkov 

机构地区：[1]Institute of Spectroscopy,Russian Academy of Sciences,Troitsk 108840,Russia [2]Faculty of Physics,Higher School of Economics,Moscow 105066,Russia [3]Key Laboratory for Physical Electronics and Devices(Ministry of Education),School of Electronic Science and Engineering,Xi’an Jiaotong University,Xi’an 710049,China [4]Quantum Technology Centre,Faculty of Physics,M.V.Lomonosov Moscow State University,Moscow 119991,Russia

出　　处：《Science Bulletin》2023年第18期2017-2024,M0003,共9页科学通报（英文版）

基　　金：supported by the research project FFUU-2021-0003 of the Institute of Spectroscopy of the Russian Academy of Sciences;partially by the Russian Science Foundation(21-12-00096);funding by the National Natural Science Foundation of China(12074308);support by the Foundation for the Advancement of Theoretical Physics and Mathematics"BASIS"(22-2-2-26-1).

摘　　要：时间参数周期变化的弗洛凯系统有助于发现常参数静态系统中不存在并常常伴有新颖拓扑态出现的非传统拓扑相.耦合系数被周期调制的Su-Schrieffer-Heeger晶格正是这种弗洛凯系统之一.尽管这个晶格在一半演化周期内处在拓扑非平庸相,在另一半周期内处于拓扑平庸相,它的边界上仍然支持源于拓扑的反常π模.本文通过在透明非线性光学材料中刻蚀出周期振荡的Su-Schrieffer-Heeger波导阵列,分别实验观测到了一维系统中位于边界和二维系统中位于角落的光学反常π模.同时,在弗洛凯频谱的禁带中,作者还证实了在高功率情况下一类分化自光学反常π模的新拓扑π孤子.本文报道的π孤子是强振荡的非线性弗洛凯态,它们的波形在每经过一个纵向周期后都可以精确地复现.不论是在一维还是在二维振荡波导阵列中,这类π孤子都是动态稳定的,它们的局域特性都由其功率决定.二维的结果还表明作者实现了弗洛凯光学高阶拓扑绝缘体.Floquet systems with periodically varying in time parameters enable realization of unconventional topological phases that do not exist in static systems with constant parameters and that are frequently accompanied by appearance of novel types of the topological states.Among such Floquet systems are the Su-Schrieffer-Heeger lattices with periodically-modulated couplings that can support at their edges anomalous p modes of topological origin despite the fact that the lattice spends only half of the evolution period in topologically nontrivial phase,while during other half-period it is topologically trivial.Here,using Su-Schrieffer-Heeger arrays composed from periodically oscillating waveguides inscribed in transparent nonlinear optical medium,we report experimental observation of photonic anomalous p modes residing at the edge or in the corner of the one-or two-dimensional arrays,respectively,and demonstrate a new class of topological p solitons bifurcating from such modes in the topological gap of the Floquet spectrum at high powers.p solitons reported here are strongly oscillating nonlinear Floquet states exactly reproducing their profiles after each longitudinal period of the structure.They can be dynamically stable in both one-and two-dimensional oscillating waveguide arrays,the latter ones representing the first realization of the Floquet photonic higher-order topological insulator,while localization properties of such p solitons are determined by their power.

关 键 词：Floquet topological insulators p states Edge solitons SSH model 

分 类 号：O469[理学—凝聚态物理]