Jiecheng Diao, Mathew Cherukara, Ross Harder, Xiaojing Huang, Fucai Zhang, Bo Chen, Andrew Ulvestad, Sanghoon Song, Diling Zhu, David Keen, Ian Robinson，“Unusual breathing behavior of optically excited Barium Titanate nanocrystals”，Crystals 10 (5), 365（2020）

【原文】

Unusual breathing behavior of optically excited Barium Titanate nanocrystals

ABSTRACT

Coherent X-ray diffraction patterns were recorded by using an X-ray free-electron laser to illuminate barium titanate nanocrystals as a function of time delay after laser excitation. Rather than seeing any significant thermal expansion effects, the diffraction peaks were found to move perpendicular to the momentum transfer direction. This suggests a laser driven rotation of the crystal lattice, which is delayed by the aggregated state of the crystals. Internal deformations associated with crystal contacts were also observed.