Catching Nanoscale Surface Vibrations with diffused x-ray scattering
In our study, together with leading groups in Fermi free electron laser in Trieste and other collaborators, we have revealed the possibility of capturing finite momentum surface vibrational modes using diffused extreme ultraviolet light. After a femtosecond laser pulse excites the surface, the diffused x-ray pulse oscillates and reveal the presence of coherent surface waves traveling in all directions.
What’s striking in our work is how broadly you could apply the technique we propose to measure surface vibrational modes in completely different materials. In this works we explore surface modes in thin metal films, thin and bulk semiconductors. The result is a surprisingly simple way to both generate and observe surface phonons far beyond the reach of traditional methods, opening a new window into how materials behave at the nanoscale.
The full paper is published on Physical Review Letters.