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Updated: May 16, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Ultrafast carrier dynamics in graphene under a high electric field
Shuntaro Tani1, François Blanchard, Koichiro Tanaka
1Department of Physics, Kyoto University, Kyoto 606-8502, Japan. tani@scphys.kyoto-u.ac.jp
Abstract:
We investigated ultrafast carrier dynamics in graphene with near-infrared transient absorption measurement after intense half-cycle terahertz pulse excitation. The terahertz electric field efficiently drives the carriers, inducing large transparency in the near-infrared region. Theoretical calculations using the Boltzmann transport equation quantitatively reproduce the experimental findings. This good agreement suggests that the intense terahertz field should promote a remarkable impact ionization process and increase the carrier density.
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