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Updated: Jun 11, 2025
08:12
Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
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Diverse Excitonic Phenomena in Asymmetric Trilayer Transition Metal Dichalcogenide Heterostructures
1School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China.
The Journal of Physical Chemistry Letters
|September 27, 2024
Summary
We explored electronic and optical properties of trilayer transition metal dichalcogenide (TMD) heterostructures. Hybridized interlayer excitons (h-IXs) were found to be optically bright with tunable lifetimes.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Chemistry
Background:
- Two-dimensional transition metal dichalcogenide (TMD) heterostructures host interlayer excitons with tunable properties due to spatial separation.
- Understanding exciton behavior in complex heterostructures is key for optoelectronic applications.
Purpose of the Study:
- Investigate the electronic and excitonic optical properties of MoS2/MoSSe/WSe2 and MoS2/MoSSe/MoSe2 trilayer heterostructures.
- Characterize various exciton states, including interlayer excitons, every-other-layer excitons, and their hybridized states (h-IXs).
Main Methods:
- Utilized state-of-the-art GW+Bethe-Salpeter Equation (BSE) calculations.
- Analyzed electronic band structures and excitonic optical properties.
Main Results:
- Discovered diverse exciton states, including interlayer, every-other-layer, and hybridized states (h-IXs) in both trilayer systems.
- Confirmed that h-IXs are optically bright due to hybridization with intralayer excitons.
- Observed radiative lifetimes for h-IXs ranging from subnanoseconds to tens of microseconds at 77 K.
- Found greater diversity of low-lying interlayer excitons in MoS2/MoSSe/MoSe2 compared to MoS2/MoSSe/WSe2.
Conclusions:
- The energy alignment, particularly via manipulating the Janus layer, is critical for achieving rich excitonic states in trilayer TMD heterostructures.
- These findings offer insights into designing novel optoelectronic devices based on tailored excitonic properties.
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