Truly chiral phonons in α-HgS observed by circularly po- larised Raman spectroscopy

Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551, Japan Department of Physics and Electronics, Osaka Prefecture University, Osaka 599-8531, Japan Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan Tokodai Institute for Element Strategy (TIES), Tokyo Institute of Technology, Tokyo 152-8551, Japan Division of Natural and Environmental Sciences, The Open University of Japan, Chiba 261-8586, Japan Institute for Molecular Science, Okazaki, Aichi 444-8585, Japan These authors contributed equally to this work ∗e-mail: satoh@phys.titech.ac.jp