Unconventional phonon spectra and obstructed edge phonon modes

作     者：Ruihan Zhang Haohao Sheng Junze Deng Zhong Fang Zhilong Yang Zhijun Wang 

作者机构：Beijing National Laboratory for Condensed Matter Physicsand Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of SciencesBeijing 100049China 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学：物理学、力学、天文学（英文版）)

年 卷 期：2024年第67卷第4期

页      面：114-118页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11974395,and 12188101) the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB33000000) the National Key R&D Program of Chain(Grant No.2022YFA1403800) the Center for Materials Genome 

主　　题：unconventional phonon spectra obstructed edge phonon mode typeⅠ&typeⅡunconventionality 

摘      要：Based on the elementary band representations(EBR),many topologically trivial materials are classified as unconventional ones(obstructed atomic limit),where the EBR decomposition for a set of electronic states is not consistent with atomic valenceelectron band *** the work,we identify that the unconventional nature can also exist in phonon spectra,where the EBR decomposition for a set of well-separated phonon modes is not consistent with atomic vibration band representations(ABR).The unconventionality has two types:typeⅠis on an empty site;and typeⅡis on an atom site with non-atomic vibration *** unconventionality is described by the nonzero real-space invariant at the *** detailed calculations show that the black phosphorus(BP)has the typeⅠunconventional phonon spectrum,while 1H-Mo Se_(2)has the typeⅡone,although their electronic structures are also ***,the obstructed phonon modes are obtained for two types of unconventional phonon spectra.