Presentation Information
[Th-A1-E-06]PT-protected topological phonons in the wide-bandgap oxide semiconductor β-Ga2O3
Byeongcheol Choe1, Seoung-Hun Kang2, Myeongjun Kang1, In-Hwan Oh3, Daisuke Ishikawa4,5, Alfred Q. R. Baron4,5, Ayman H. Said6, Andrea Piovano7, Alexandre Ivanov7, Devashibhai Adroja8, Viviane Antonio8, Kazuki Iida9, Kazuya Kamazawa9, Katsuki Kinjo10, Kazuhiro Nawa10, Taku J. Sato10, Jaegwang Lee1, Jong Mok Ok1, Sungkyun Park1, 〇Jitae T. Park11 (1. Pusan National Univ. (Korea), 2. Kyung Hee Univ. (Korea), 3. Korea Atomic Energy Res. Inst. (Korea), 4. RIKEN SPring-8 Center (Japan), 5. SPring-8/JASRI (Japan), 6. Advanced Photon Source, Argonne National Lab. (USA), 7. Inst. Laue–Langevin (France), 8. ISIS Neutron and Muon Source, Rutherford Appleton Lab. (UK), 9. Neutron Sci. and Tech. Center, Comprehensive Res. Organization for Sci. and Society (Japan), 10. Inst. of Multidisciplinary Res. for Advanced Materials, Tohoku Univ. (Japan), 11. Technical Univ. of Munich (Germany))
We report topological phonons in β-Ga2O3 using INS and IXS. We identify band crossings near X1 with a symmetry indicator Z4=1, indicating a nontrivial state. Dynamic structure factor analysis confirms the non-trivial Berry phase. This highlights Ga2O3 as a platform for intrinsic phononic topology.