Parts | Days | Selection | Search | Updates | Downloads | Help
SYUE: Symposium Ultrafast Excitation Pathways of Quantum Materials
SYUE 1: Ultrafast Excitation Pathways of Quantum Materials
SYUE 1.2: Invited Talk
Wednesday, March 29, 2023, 10:00–10:30, HSZ 01
Accessing the nonthermal phonon populations in 2D materials with femtosecond electron diffuse scattering — •Hélène Seiler1,2, Marios Zacharias1,3, Daniela Zahn1, Patrick-Nigel Hildebrandt1, Thomas Vasileiadis1, Yoav William Windsor1,4, Yingpeng Qi1, Christian Carbogno1, Claudia Draxl5, Ralph Ernstorfer1,4, and Fabio Caruso6 — 1Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Germany — 2Freie Universität Berlin, Berlin, Germany — 3INSA de Rennes, 35708 Rennes, France — 4Technische Universität Berlin, Berlin, Germany — 5Humboldt-Universität zu Berlin, Berlin, Germany — 6Christian-Albrechts-Universität zu Kiel, Kiel, Germany
Femtosecond electron diffuse scattering (FEDS) is a powerful technique to access nonthermal phonon populations in photo-excited materials. We perform FEDS experiments to study the microscopic energy flow in two prototypical 2D materials, black phosphorus and MoS2. The experiments are complemented by first-principles calculations of the coupled electron-phonon dynamics based on the time-dependent Boltzmann equations. We also introduce an efficient first-principles methodology for the calculation of the all-phonon inelastic scattering in solids, and demonstrate its broad applicability to other 2D materials. Our joint experimental-theoretical approach provides a detailed picture of nonthermal phonons in photo-excited materials.