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Twist-assisted optoelectronic phase control in two-dimensional (2D) Janus heterostructures.
S Kar1, P Kumari1, M Venkata Kamalakar2
1Department of Physics, Indian Institute of Technology Patna, Bihta, 801103, India.
Scientific Reports
|August 22, 2023
Summary
Atomically thin Janus materials and their heterostructures show promise for electronic devices. Twist engineering enhances their stability, electronic, and optical properties, enabling tunable performance for future photovoltaic applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Two-dimensional (2D) Janus materials and their Van der Waals heterostructures (vdWHs) are novel semiconductors.
- These materials offer versatile applications in electronic and optoelectronic devices.
Purpose of the Study:
- Investigate the structural, electronic, and optical properties of inhomogeneous heterostructures.
- Explore the impact of twist engineering on the performance of these vdWHs.
Main Methods:
- First-principles calculations were employed to study heterostructures.
- Transition metal dichalcogenides (TMDs) like MoS2, WS2, MoSe2, WSe2 were combined with Janus TMDs (MoSeTe, WSeTe).
- Twist engineering was applied to vdWHs with twist angles ranging from 0° to 60°.
Main Results:
- All investigated vdWHs demonstrated dynamic and thermodynamic stability.
- Specific vdWHs exhibited direct bandgaps and type-II band alignment at certain twist angles, suitable for photovoltaics.
- Electronic properties, carrier mobility, and optical absorption were significantly tuned through interlayer coupling and twisting.
Conclusions:
- Interlayer twisting offers a novel route to modulate electronic and optoelectronic properties of Janus vdWHs.
- These engineered heterostructures hold potential for advanced electronic and optoelectronic device applications.
- The study highlights the tunability and stability of twisted Janus vdWHs for future technologies.
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