Observation of an acoustic topological Euler insulator with meronic waves

Bin Jiang ¹Adrien Bouhon ²Shi-Qiao Wu ³Ze-Lin Kong ³Zhi-Kang Lin ³Robert-Jan Slager ⁴Jian-Hua Jiang¹

扫码查看

作者信息

1. 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
2. TCM Group,Cavendish Laboratory,University of Cambridge,Cambridge CB3 0HE,UK;NORDITA,Stockholm University and KTH Royal Institute of Technology,Stockholm SE-106 91,Sweden
3. School of Physical Science and Technology & Collaborative Innovation Center of Suzhou Nano Science and Technology,Soochow University,Suzhou 215006,China
4. TCM Group,Cavendish Laboratory,University of Cambridge,Cambridge CB3 0HE,UK
折叠

Abstract

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.

Key words

Euler insulators/Meronic waves/Acoustic metamaterials/Topological phases of matter

引用本文复制引用

基金项目

National Key R&D Program of China(2022YFA1404400)

National Natural Science Foundation of China(12125504)

National Natural Science Foundation of China(12074281)

the"Hundred Talents Program"of the Chinese Academy of Sciences()

Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions()

Marie-Curie fellowship(101025315)

Swedish Research Council(Vetenskapsradet)(2021-04681)

New Investigator Award,EPSRC(EP/W00187X/1)

EPSRC ERC underwrite(EP/X025829/1)

Royal Society exchange(IES/R1/221060)

Trinity College,Cambridge()

出版年

2024

科学通报(英文版)

中国科学院

科学通报(英文版)

CSTPCD

ISSN：1001-6538

段落导航