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Updated: Jul 8, 2025

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Ultrafast Transition from State-Blocking Dynamics to Electron Localization in Transition Metal β-Tungsten
E W de Vos1, S Neb1, A Niedermayr1
1Department of Physics, ETH Zürich, 8093 Zürich, Switzerland.
Abstract:
We describe an ultrafast transition of the electronic response of optically excited transition metal β-tungsten with few-femtosecond time resolution. The response moves from a regime where state filling of the excited carrier population around the Fermi level dominates towards localization of carriers onto the outer d orbitals. This is in contrast to previous measurements using ultrafast element-specific core-level spectroscopy enabled by attosecond transient absorption spectroscopy on transition metals such as titanium and around the transition metal atom in transition metal dichalchogenides MoTe_{2} and MoSe_{2}. This surprisingly different dynamical response for β-tungsten can be explained by considering the electron-electron dynamics on a few-femtosecond timescale and the slower electron-phonon thermalization dynamics.
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