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Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
Observation of Ultrafast Free Carrier Dynamics in Single Layer MoS2
Antonija Grubišić Čabo1, Jill A Miwa1, Signe S Grønborg1
1Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University , 8000 Aarhus C, Denmark.
Abstract:
The dynamics of excited electrons and holes in single layer (SL) MoS2 have so far been difficult to disentangle from the excitons that dominate the optical response of this material. Here, we use time- and angle-resolved photoemission spectroscopy for a SL of MoS2 on a metallic substrate to directly measure the excited free carriers. This allows us to ascertain a direct quasiparticle band gap of 1.95 eV and determine an ultrafast (50 fs) extraction of excited free carriers via the metal in contact with the SL MoS2. This process is of key importance for optoelectronic applications that rely on separated free carriers rather than excitons.
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