Hot carrier dynamics in MoS2/WS2heterostructure.
Lang Zhu1, Zongpeng Song1,2, Ran Li1
1New Materials and New Energies, Shen Zhen Technology University, Shenzhen, 518118, People's Republic of China.
Nanotechnology
|January 24, 2022
Summary
Hot carriers in molybdenum disulfide/tungsten disulfide (MoS2/WS2) heterostructures can be rapidly separated and effectively re-injected. This process compensates for carrier loss, significantly improving light utilization in optoelectronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Transition metal dichalcogenides (TMDs) heterostructures show promise for photoelectric devices due to efficient carrier separation and long exciton lifetimes.
- Existing research on TMDs heterostructures primarily examines carrier transfer and exciton lifetimes, neglecting hot carrier dynamics.
Purpose of the Study:
- Investigate the dynamics of hot carriers in MoS2/WS2 heterostructures.
- Understand the role of hot carriers in enhancing optoelectronic device performance.
Main Methods:
- Transient absorption spectroscopy was employed to study carrier dynamics.
- Analysis focused on the behavior of photo-generated carriers and excitons.
Main Results:
- Observed rapid separation of electrons and holes.
- Identified intervalley transfer of hot carriers from C excitons.
- Demonstrated that hot carriers compensate for carrier loss in band edge excitons.
Conclusions:
- Hot carrier dynamics, specifically intervalley transfer, are crucial for optoelectronic applications.
- The re-injection of hot carriers can significantly improve light utilization efficiency in devices.
- This finding opens new avenues for designing high-performance optoelectronic devices.
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