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Updated: Jun 21, 2025
09:25
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
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Infrared Interlayer Excitons in Twist-Free MoTe2/MoS2 Heterobilayers
Qiankun Ju1,2, Qian Cai1, Chuanyong Jian1
1CAS Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Provincial Key Laboratory of Materials and Techniques toward Hydrogen Energy, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|July 15, 2024
Summary
Researchers achieved crucial telecom C-band exciton emission in MoTe2/MoS2 heterobilayers. This breakthrough enables efficient excitonic devices for silicon photonics and all-optical telecommunications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Optoelectronics
Background:
- Excitonic devices using van der Waals heterobilayers show promise for photoelectric interconnection telecommunications.
- A key limitation is the lack of exciton emission in the telecom C-band, hindering practical applications.
Purpose of the Study:
- To achieve and characterize exciton emission in the telecom C-band for advanced photoelectric devices.
- To investigate the properties and control of interlayer excitons in van der Waals heterobilayers.
Main Methods:
- Fabrication of a chemically vapor-deposited, strictly aligned MoTe2/MoS2 heterobilayer.
- Momentum-space imaging to identify direct bandgap transitions of interlayer excitons.
- Characterization of spin-orbit coupling effects and Landé g-factors.
Main Results:
- Demonstrated exciton emission at 0.8 eV (1550 nm) within the telecom C-band.
- Observed two narrowly-split transitions due to spin-orbit coupling, confirmed by distinct Landé g-factors.
- Achieved electrical control of circularly-polarized photon modes with up to 90% polarization.
- Extended emission energy by over 150 meV using Stark effect tuning.
Conclusions:
- The study provides a viable material platform for excitonic devices operating in the telecom C-band.
- Findings significantly enhance the application prospects of excitonic devices in silicon photonics and all-optical telecommunications.
- The controlled manipulation of exciton properties opens new avenues for fundamental studies of excitonic complexes.
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