报告题目:First-principles study on the finite-temperature phonon anomalies in PbTe
主 讲 人:Yue Chen (陈粤)
Assistant Professor of Materials Science and Engineering
Department of Mechanical Engineering
The University of Hong Kong
时 间:8月15日(周五)下午14:00
地 点:师昌绪楼 403 会议室
摘要:
In this talk, I will introduce a new approach to compute the finite temperature lattice dynamics from first-principles via the newly developed slave mode expansion. We study PbTe where inelastic neutron scattering (INS) reveals strong signatures of nonlinearity as evidenced by anomalous features which emerge in the phonon spectra at finite temperature. Using our slave mode expansion in the classical limit, we compute the vibrational spectra and show remarkable agreement with temperature dependent INS measurements. Furthermore, we resolve experimental controversy by showing that there are no appreciable local nor global spontaneously broken symmetries at finite temperature and that the anomalous spectral features simply arise from two anharmonic interactions. Our approach should be broadly applicable across the periodic table.
简介:
Yue Chen is an Assistant Professor of Materials Science and Engineering at the University of Hong Kong. He obtained his PhD degree in 2010 after finishing a joint program between University of Oxford and Beihang University. Before joining HKU, he was a postdoc at Columbia University and Institute of Metal Research, CAS. His research interest is in solving anomalous materials behaviors through first-principles calculations.
欢迎所内广大职工及研究生前来交流!