Fermi Pressure and Coulomb Repulsion Driven Rapid Hot Plasma Expansion in a van der Waals Heterostructure.

Autor: Choi J; Department of Physics and Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, United States., Embley J; Department of Physics and Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, United States., Blach DD; Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2050, United States., Perea-Causín R; Department of Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden., Erkensten D; Department of Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden., Kim DS; Department of Physics and Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, United States., Yuan L; Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2050, United States., Yoon WY; Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712, United States., Taniguchi T; International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan., Watanabe K; Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan., Ueno K; Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan., Tutuc E; Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712, United States., Brem S; Department of Physics, Philipps University of Marburg, 35037 Marburg, Germany., Malic E; Department of Physics, Chalmers University of Technology, 41296 Gothenburg, Sweden.; Department of Physics, Philipps University of Marburg, 35037 Marburg, Germany., Li X; Department of Physics and Center for Complex Quantum Systems, The University of Texas at Austin, Austin, Texas 78712, United States., Huang L; Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2050, United States.
Jazyk: angličtina
Zdroj: Nano letters [Nano Lett] 2023 May 24; Vol. 23 (10), pp. 4399-4405. Date of Electronic Publication: 2023 May 08.
DOI: 10.1021/acs.nanolett.3c00678
Abstrakt: Transition metal dichalcogenide heterostructures provide a versatile platform to explore electronic and excitonic phases. As the excitation density exceeds the critical Mott density, interlayer excitons are ionized into an electron-hole plasma phase. The transport of the highly non-equilibrium plasma is relevant for high-power optoelectronic devices but has not been carefully investigated previously. Here, we employ spatially resolved pump-probe microscopy to investigate the spatial-temporal dynamics of interlayer excitons and hot-plasma phase in a MoSe 2 /WSe 2 twisted bilayer. At the excitation density of ∼10 14 cm -2 , well exceeding the Mott density, we find a surprisingly rapid initial expansion of hot plasma to a few microns away from the excitation source within ∼0.2 ps. Microscopic theory reveals that this rapid expansion is mainly driven by Fermi pressure and Coulomb repulsion, while the hot carrier effect has only a minor effect in the plasma phase.
Databáze: MEDLINE