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Updated: Jul 16, 2025
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Preparation of Large-area Vertical 2D Crystal Hetero-structures Through the Sulfurization of Transition Metal Films for Device Fabrication
Published on: November 28, 2017
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Interlayer donor-acceptor pair excitons in MoSe2/WSe2 moiré heterobilayer
Hongbing Cai1,2, Abdullah Rasmita1, Qinghai Tan1
1Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
Nature Communications
|September 18, 2023
Summary
Localized interlayer excitons (LIXs) in moiré superlattices are promising single-photon sources. We reveal the donor-acceptor pair (DAP) mechanism as a key origin of these excitonic peaks.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Optics
Background:
- Two-dimensional (2D) moiré superlattices enable novel quantum phenomena.
- Localized interlayer excitons (LIXs) in these systems show potential for single-photon sources.
- The fundamental mechanisms governing LIX properties remain largely unexplored.
Purpose of the Study:
- To elucidate the physical origin of localized interlayer excitons (LIXs) in 2D moiré heterostructures.
- To investigate the donor-acceptor pair (DAP) mechanism as a potential source of LIX emission.
- To correlate experimental observations with theoretical models for LIX formation.
Main Methods:
- Experimental photoluminescence spectroscopy of LIXs in moiré MoSe2/WSe2 heterobilayers.
- Numerical simulations based on the donor-acceptor pair (DAP) model.
- Analysis of emission energy-lifetime correlations and power-dependent lifetime measurements.
Main Results:
- The donor-acceptor pair (DAP) mechanism is identified as a significant contributor to LIX peaks.
- Numerical simulations of the DAP model show strong agreement with experimental photoluminescence spectra.
- Observed emission energy-lifetime correlations and nonmonotonic power dependencies align with the DAP exciton model.
Conclusions:
- The DAP mechanism provides a crucial understanding of LIX formation in moiré heterostructures.
- This finding offers insights into the fundamental physics of excitonic phenomena in van der Waals materials.
- The study opens avenues for engineering LIX properties for advanced quantum applications.
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