Browsing by Author "Vorobiev, A."

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Unveiling the plasma wave in the channel of graphene field-effect transistor
    (2019-09-01) Soltani, A.; Kuschewski, F.; Bonmann, M.; Generalov, A.; Vorobiev, A.; Ludwig, F.; Wiecha, M.; Cibiraite, D.; Walla, F.; Kehr, S. C.; Eng, L. M.; Stake, J.; Roskos, H. G.; Department of Electronics and Nanoengineering; Centre of Excellence in Quantum Technology, QTF; Zhipei Sun Group; Goethe University Frankfurt; Technische Universität Dresden; Chalmers University of Technology
    Coupling an electromagnetic wave at GHz to THz frequencies into the channel of a graphene field-effect transistor (GFET) provokes collective charge carrier oscillations of the two-dimensional electron gas (2DEG) known as plasma waves. Here, we report the very first experimental and direct mapping of the electric field distribution in a gated GFET at nanometer length scales using scattering-type scanning near-field microscopy (s-SNOM) at 2 THz. Based on the experimental results we deduce the plasma wave velocity for different gate bias voltages, which is in good agreement with the theoretical prediction.