Observation of nonlinear disclination states  

作　　者：Boquan Ren Antonina A.Arkhipova Yiqi Zhang Yaroslav V.Kartashov Hongguang Wang 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]Key Laboratory for Physical Electronics and Devices,Ministry of Education,School of Electronic Science and Engineering,Xi’an Jiaotong University,Xi’an 710049,China [2]Institute of Spectroscopy,Russian Academy of Sciences,Troitsk,Moscow 108840,Russia [3]Faculty of Physics,Higher School of Economics,Moscow 105066,Russia [4]Quantum Technology Centre,Faculty of Physics,M.V.Lomonosov Moscow State University,Moscow 119991,Russia

出　　处：《Light(Science & Applications)》2023年第9期1818-1829,共12页光（科学与应用)（英文版）

基　　金：B.R.,H.W.and Y.Z.acknowledge funding by the National Natural Science Foundation of China(Grant No.:12074308);the Fundamental Research Funds for the Central Universities(Grant No.:xzy022022058);A.A.A.,Y.V.K.,S.A.Z.,N.N.S.,A.A.K.,V.O.K.,S.V.C.,and V.N.Z.acknowledge funding by the Russian Science Foundation grant 21-12-00096;the research project FFUU2021-0003 of the Institute of Spectroscopy of the Russian Academy of Sciences.A.A.K;S.P.K.are supported by the Ministry of Science and Higher Education of the Russian Federation on the basis of the FSAEIHE SUSU(NRU)(Agreement No.:075-15-2022-1116).

摘　　要：Introduction of controllable deformations into periodic materials that lead to disclinations in their structure opens novel routes for construction of higher-order topological insulators hosting topological states at disclinations.Appearance of these topological states is consistent with the bulk-disclination correspondence principle,and is due to the filling anomaly that results in fractional charges to the boundary unit cells.So far,topological disclination states were observed only in the linear regime,while the interplay between nonlinearity and topology in the systems with disclinations has been never studied experimentally.We report here on the experimental observation of the nonlinear photonic disclination states in waveguide arrays with pentagonal or heptagonal disclination cores inscribed in transparent optical medium using the fs-laser writing technique.The transition between nontopological and topological phases in such structures is controlled by the Kekulédistortion coefficient r with topological phase hosting simultaneously disclination states at the inner disclination core and spatially separated from them corner-I,corner-II,and extended edge states at the outer edge of the structure.We show that the robust nonlinear disclination states bifurcate from their linear counterparts and that location of their propagation constants in the gap and,hence,their spatial localization can be controlled by their power.Nonlinear disclination states can be efficiently excited by Gaussian input beams,but only if they are focused into the waveguides belonging to the disclination core,where such topological states reside.Our results open new prospects for investigation of nonlinear effects in topological systems with disclinations and are relevant for different areas of science,including Bose-Einstein and polariton condensates,where potentials with the disclinations can be created.

关 键 词：STRUCTURE TOPOLOGICAL NONLINEAR 

分 类 号：O17[理学—数学]