具有半子模式欧拉拓扑绝缘体的声学观测  

Observation of an acoustic topological Euler insulator with meronicwaves

作　　者：姜斌 Adrien Bouhon 吴世巧 孔泽霖 林志康 Robert-Jan Slager 蒋建华 Bin Jiang;Adrien Bouhon;Shi-Qiao Wu;Ze-Lin Kong;Zhi-Kang Lin;Robert-Jan Slager;Jian-Hua Jiang(Suzhou Institute for Advanced Research,University of Science and Technology of China,Suzhou 215123,China;School of Physical Science and Technology&Collaborative Innovation Center of Suzhou Nano Science and Technology,Soochow University,Suzhou 215006,China;TCM Group,Cavendish Laboratory,University of Cambridge,Cambridge CB30HE,UK;NORDITA,Stockholm University and KTH Royal Institute of Technology,Stockholm SE-10691,Sweden)

机构地区：[1]Suzhou Institute for Advanced Research,University of Science and Technology of China,Suzhou 215123,China [2]School of Physical Science and Technology&Collaborative Innovation Center of Suzhou Nano Science and Technology,Soochow University,Suzhou 215006,China [3]TCM Group,Cavendish Laboratory,University of Cambridge,Cambridge CB30HE,UK [4]NORDITA,Stockholm University and KTH Royal Institute of Technology,Stockholm SE-10691,Sweden

出　　处：《Science Bulletin》2024年第11期1653-1659,共7页科学通报（英文版）

基　　金：the National Key R&D Program of China (2022YFA1404400);the National Natural Science Foundation of China (12125504 and 12074281);the “Hundred Talents Program” of the Chinese Academy of Sciences;the Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions;partially funded by a Marie-Curie fellowship (101025315);financial support from the Swedish Research Council (Vetenskapsradet) (2021-04681);funding from a New Investigator Award,EPSRC grant EP/W00187X/1;EPSRC ERC underwrite grant EP/X025829/1;a Royal Society exchange grant IES/ R1/221060;Trinity College,Cambridge。

摘　　要：Topological band theory has conventionally been concerned with the topology of bands around a single gap. Only recently non-Abelian topologies that thrive on involving multiple gaps were studied, unveiling a new horizon in topological physics beyond the conventional paradigm. Here, we report on the first experimental realization of a topological Euler insulator phase with unique meronic characterization in an acoustic metamaterial. We demonstrate that this topological phase has several nontrivial features:First, the system cannot be described by conventional topological band theory, but has a nontrivial Euler class that captures the unconventional geometry of the Bloch bands in the Brillouin zone.Second, we uncover in theory and probe in experiments a meronic configuration of the bulk Bloch states for the first time. Third, using a detailed symmetry analysis, we show that the topological Euler insulator evolves from a non-Abelian topological semimetal phase via. the annihilation of Dirac points in pairs in one of the band gaps. With these nontrivial properties, we establish concretely an unconventional bulk-edge correspondence which is confirmed by directly measuring the edge states via. pump-probe techniques. Our work thus unveils a nontrivial topological Euler insulator phase with a unique meronic pattern and paves the way as a platform for non-Abelian topological phenomena.

关 键 词：Euler insulators Meronic waves Acoustic metamaterials Topological phases of matter 

分 类 号：O469[理学—凝聚态物理]