Lin, Ming-FuKochat, VidyaKrishnamoorthy, AravindBassman, LindsayWeninger, ClemensZheng, QiangZhang, XiangApte, AmeyTiwary, Chandra SekharShen, XiaozheLi, RenkaiKalia, RajivAjayan, PulickelNakano, AiichiroVashishta, PriyaShimojo, FuyukiWang, XijieFritz, David M.Bergmann, Uwe2017-12-182017-12-182017Lin, Ming-Fu, Kochat, Vidya, Krishnamoorthy, Aravind, et al.. "Ultrafast non-radiative dynamics of atomically thin MoSe2." <i>Nature Communications,</i> 8, (2017) Springer Nature: https://doi.org/10.1038/s41467-017-01844-2.https://hdl.handle.net/1911/98888Photo-induced non-radiative energy dissipation is a potential pathway to induce structural-phase transitions in two-dimensional materials. For advancing this field, a quantitative understanding of real-time atomic motion and lattice temperature is required. However, this understanding has been incomplete due to a lack of suitable experimental techniques. Here, we use ultrafast electron diffraction to directly probe the subpicosecond conversion of photoenergy to lattice vibrations in a model bilayered semiconductor, molybdenum diselenide. We find that when creating a high charge carrier density, the energy is efficiently transferred to the lattice within one picosecond. First-principles nonadiabatic quantum molecular dynamics simulations reproduce the observed ultrafast increase in lattice temperature and the corresponding conversion of photoenergy to lattice vibrations. Nonadiabatic quantum simulations further suggest that a softening of vibrational modes in the excited state is involved in efficient and rapid energy transfer between the electronic system and the lattice.engThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Journal articleUltrafast-non-radiative-dynamicshttps://doi.org/10.1038/s41467-017-01844-2