Brillouin Klein space and half-turn space in three-dimensional acoustic crystals  

作　　者：Zhenxiao Zhu Linyun Yang Jien Wu Yan Meng Xiang Xi Bei Yan Jingming Chen Jiuyang Lu Xueqin Huang Weiyin Deng Ce Shang Perry Ping Shum Yihao Yang Hongsheng Chen Kexin Xiang Gui-Geng Liu Zhengyou Liu Zhen Gao 

机构地区：[1]State Key Laboratory of Optical Fiber and Cable Manufacture Technology,Department of Electronic and Electrical Engineering,Southern University of Science and Technology,Shenzhen 518055,China [2]School of Physics and Optoelectronics,South China University of Technology,Guangzhou 510640,China [3]Key Laboratory of Artificial Micro-and Nanostructures of Ministry of Education and School of Physics and Technology,Wuhan University,Wuhan 430072,China [4]King Abdullah University of Science and Technology(KAUST),Physical Science and Engineering Division(PSE),Thuwal 23955-6900,Saudi Arabia [5]Interdisciplinary Center for Quantum Information,State Key Laboratory of Modern Optical Instrumentation,ZJU-Hangzhou Global Science and Technology Innovation Center,College of Information Science and Electronic Engineering,ZJU-UIUC Institute,Zhejiang University,Hangzhou 310027,China [6]Division of Physics and Applied Physics,School of Physical and Mathematical Sciences,Nanyang Technological University,Singapore 637371,Singapore [7]Institute for Advanced Studies,Wuhan University,Wuhan 430072,China

出　　处：《Science Bulletin》2024年第13期2050-2058,共9页科学通报（英文版）

基　　金：funding from the National Natural Science Foundation of China(62375118,6231101016,and 12104211);Shenzhen Science and Technology Innovation Commission(20220815111105001);SUSTech(Y01236148 and Y01236248);Zhengyou Liu acknowledges funding from the National Key R&D Program of China(2022YFA1404900 and 2018YFA0305800);the National Natural Science Foundation of China(11890701);the National Natural Science Foundation of China(12304484);Basic and Applied Basic Research Foundation of Guangdong Province(2414050002552);Shenzhen Science and Technology Innovation Commission(202308073000209);Perry Ping Shum acknowledges the National Natural Science Foundation of China(62220106006);Shenzhen Science and Technology Program(SGDX20211123114001001);Kexin Xiang acknowledges the Special Funds for the Cultivation of Guangdong College Students’Scientific and Technological Innovation(pdjh2023c21002).

摘　　要：The Bloch band theory and Brillouin zone(BZ)that characterize wave-like behaviors in periodic mediums are two cornerstones of contemporary physics,ranging from condensed matter to topological physics.Recent theoretical breakthrough revealed that,under the projective symmetry algebra enforced by artificial gauge fields,the usual two-dimensional(2D)BZ(orientable Brillouin two-torus)can be fundamentally modified to a non-orientable Brillouin Klein bottle with radically distinct manifold topology.However,the physical consequence of artificial gauge fields on the more general three-dimensional(3D)BZ(orientable Brillouin three-torus)was so far missing.Here,we theoretically discovered and experimentally observed that the fundamental domain and topology of the usual 3D BZ can be reduced to a non-orientable Brillouin Klein space or an orientable Brillouin half-turn space in a 3D acoustic crystal with artificial gauge fields.We experimentally identify peculiar 3D momentum-space non-symmorphic screw rotation and glide reflection symmetries in the measured band structures.Moreover,we experimentally demonstrate a novel stacked weak Klein bottle insulator featuring a nonzero Z2 topological invariant and self-collimated topological surface states at two opposite surfaces related by a nonlocal twist,radically distinct from all previous 3D topological insulators.Our discovery not only fundamentally modifies the fundamental domain and topology of 3D BZ,but also opens the door towards a wealth of previously overlooked momentum-space multidimensional manifold topologies and novel gaugesymmetry-enriched topological physics and robust acoustic wave manipulations beyond the existing paradigms.

关 键 词：Momentum-space non-symmorphic symmetry Brillouin Klein space and half-turn space Acoustic Klein bottle insulator Self-collimated topological surface states 

分 类 号：O18[理学—数学]