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Kriegel_et_al_MoS2_ITO_hybrids.pdf (2.36 MB)
0D Nanocrystals as Light-Driven, Localized Charge Injection Sources for the Contactless Manipulation of Atomically Thin 2D Materials
Preprints are manuscripts made publicly available before they have been submitted for formal peer review and publication. They might contain new research findings or data. Preprints can be a draft or final version of an author's research but must not have been accepted for publication at the time of submission.
submitted on 12.08.2020 and posted on 12.08.2020by Ilka Kriegel, Michele Ghini, Emanuil Sashev Yanev, Christoph Kastl, Adam W. Jansons, Brandon M. Crockett, Kristopher M. Koskela, Edward S. Barnard, Erika Penzo, James Evan Hutchison, Joshua. A. Robinson, Liberato Manna, Nicholas J. Borys, P. James Schuck
We report a new localized and electrodeless charge injection scheme that quasi-permanently modifies
monolayer (1L-)MoS2 doping levels to extents competing with electrostatic gating. The key innovation
is to use Sn-doped In2O3 (ITO) nanocrystals (NCs) as contactless light-driven charge injection sources
triggered solely by light. Each nanocrystal can store and transfer multiple charges after ultraviolet
illumination within the diffraction limited laser spot. This results in reductions in carrier density in the
underlying 1L-MoS2 up to 1×1013 cm-2
and is observed throughout the extent of the 2D material flake.
The long-distance charge separation proliferates up to 40 µm away from the localized charge injection
and persists over months. The apparent driving force for carrier relocation is the initial inhomogeneous
electronic landscape of the 2D material. These studies demonstrate a novel all-optically controlled tool
to locally inject carriers with sub-micrometer precision. This new ability allows us to extract important
aspects of inhomogeneity in 2D materials undisturbed by bulky electronic contacts and indicates that
local 2D material manipulation can serve as a key element for novel nanoscale device design.