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Title: Size-tunable Lateral Confinement in Monolayer Semiconductors

Three-dimensional confinement allows semiconductor quantum dots to exhibit size-tunable electronic and optical properties that enable a wide range of opto-electronic applications from displays, solar cells and bio-medical imaging to single-electron devices. Additional modalities such as spin and valley properties in monolayer transition metal dichalcogenides provide further degrees of freedom requisite for information processing and spintronics. In nanostructures, however, spatial confinement can cause hybridization that inhibits the robustness of these emergent properties. Here in this paper, we show that laterally-confined excitons in monolayer MoS 2 nanodots can be created through top-down nanopatterning with controlled size tunability. Unlike chemically-exfoliated monolayer nanoparticles, the lithographically patterned monolayer semiconductor nanodots down to a radius of 15 nm exhibit the same valley polarization as in a continuous monolayer sheet. The inherited bulk spin and valley properties, the size dependence of excitonic energies, and the ability to fabricate MoS 2 nanostructures using semiconductor-compatible processing suggest that monolayer semiconductor nanodots have potential to be multimodal building blocks of integrated optoelectronics and spintronics systems
 [1] ;  [2] ;  [3] ;  [3] ;  [2] ; ORCiD logo [4]
  1. Northwestern Univ., Evanston, IL (United States). Applied Physics Program
  2. Argonne National Lab. (ANL), Argonne, IL (United States). Center for Nanoscale Materials
  3. Northwestern Univ., Evanston, IL (United States). Dept. of Physics and Astronomy
  4. Northwestern Univ., Evanston, IL (United States). Applied Physics Program; Northwestern Univ., Evanston, IL (United States). Dept. of Physics and Astronomy
Publication Date:
Grant/Contract Number:
AC02-06CH11357; SC0012130
Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322
Nature Publishing Group
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
Country of Publication:
United States
77 NANOSCIENCE AND NANOTECHNOLOGY; Electronic properties and materials; Nanoparticles; Quantum dots; Two-dimensional materials
OSTI Identifier: