Picosecond Electronic and Structural Dynamics in Photoexcited Monolayer MoSe<sub>2</sub>
ORAL
Abstract
Monolayers of semiconducting transition metal dichalcogenides (TMDC) are emerging as strong candidate materials for next generation electronic and optoelectronic devices. Prior studies have demonstrated strong light-matter interactions in these materials which suggests optical control of material properties is a promising route for their functionalization. However, the electronic and structural dynamics in response to electronic excitation have not yet been fully elucidated. In this work, we use non-adiabatic quantum molecular dynamics based on time-dependent density functional theory to study lattice dynamics of a model TMDC monolayer of MoSe2 after electronic excitation and explore the dependence of dynamics on photo-generated electron-hole density. We observe phonon mode softening induced by Fermi-surface nesting, as well as increasing lattice disorder, as measured by the Debye-Waller factor (DWF), with increasing excitation. Furthermore, we find a transition from single-exponential to bi-exponential decay of the DWF at higher electron-hole densities.
*This work was supported as part of the Computational Materials Sciences Program funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award Number DE-SC00014607.
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Presenters
Lindsay Bassman
University of Southern California
Physics, University of Southern California
Authors
Lindsay Bassman
University of Southern California
Physics, University of Southern California
Aravind Krishnamoorthy
Physics & Astronomy, University of Southern California
Univ of Southern California
Physics, University of Southern California
University of Southern California
Rajiv Kalia
Univ of Southern California
Physics & Astronomy, University of Southern California
University of Southern California
Mork Family Department of Chemical Engineering and Materials Science, Univ of Southern California
Collaboratory of Advanced Computing and Simulations, Univ of Southern California
Collaboratory for Advanced Computing and Simulations, University of Southern California
Physics, University of Southern California
Aiichiro Nakano
Univ of Southern California
Physics & Astronomy, University of Southern California
University of Southern California
Mork Family Department of Chemical Engineering and Materials Science, Univ of Southern California
Collaboratory of Advanced Computing and Simulations, Univ of Southern California
Physics, University of Southern California
Priya Vashishta
Univ of Southern California
Physics & Astronomy, University of Southern California
University of Southern California
Mork Family Department of Chemical Engineering and Materials Science, Univ of Southern California
Collaboratory of Advanced Computing and Simulations, Univ of Southern California
Collaboratory for Advanced Computing and Simulations, University of Southern California
