Direct Visualization of Subnanometer Variations in the Excitonic Spectra of 2D/3D Semiconductor/Metal Heterostructures
Name
EELS_nanoARPES_excitons_resub_clean_final*.pdf
Size
4.64 MB
Format
Adobe PDF
Checksum (MD5)
7c701b236b72a055692a1e30d81c1386
Author(s)
Reidy, Kate
Majchrzak, Paulina Ewa
Haas, Benedikt
Thomsen, Joachim Dahl
Konečná, Andrea
Park, Eugene
Klein, Julian
Jones, Alfred J. H.
Volckaert, Klara
Biswas, Deepnarayan
Date Issued
January 13, 2023
Journal
Nano Letters
Publisher
American Chemical Society
Citation
Reidy, Kate, Majchrzak, Paulina Ewa, Haas, Benedikt, Thomsen, Joachim Dahl, Konečná, Andrea et al. 2023. "Direct Visualization of Subnanometer Variations in the Excitonic Spectra of 2D/3D Semiconductor/Metal Heterostructures." Nano Letters, 23 (3).
Version
Author's final manuscript
Abstract
The integration of metallic contacts with two-dimensional (2D) semiconductors is routinely required for the fabrication of nanoscale devices. However, nanometer-scale variations in the 2D/metal interface can drastically alter the local optoelectronic properties. Here, we map local excitonic changes of the 2D semiconductor MoS2 in contact with Au. We utilize a suspended and epitaxially grown 2D/metal platform that allows correlated electron energy-loss spectroscopy (EELS) and angle resolved photoelectron spectroscopy (nanoARPES) mapping. Spatial localization of MoS2 excitons uncovers an additional EELS peak related to the MoS2/Au interface. NanoARPES measurements indicate that Au–S hybridization decreases substantially with distance from the 2D/metal interface, suggesting that the observed EELS peak arises due to dielectric screening of the excitonic Coulomb interaction. Our results suggest that increasing the van der Waals distance could optimize excitonic spectra of mixed-dimensional 2D/3D interfaces and highlight opportunities for Coulomb engineering of exciton energies by the local dielectric environment or moiré engineering.
Subjects
Mechanical Engineering
Condensed Matter Physics
General Materials Science
General Chemistry
Bioengineering
MIT Department
Massachusetts Institute of Technology. Department of Materials Science and Engineering
Terms of Use
Creative Commons Attribution-Noncommercial-ShareAlike
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DOI of Published Version
https://doi.org/10.1021/acs.nanolett.2c04749
