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Updated: Mar 22, 2026
09:25
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
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Strain-Induced Electronic Structure Changes in Stacked van der Waals Heterostructures.
Yongmin He1,2, Yang Yang1, Zhuhua Zhang1,3
1Department of Materials Science and NanoEngineering, Rice University , Houston, Texas 77005, United States.
Nano Letters
|April 28, 2016
Summary
Directly synthesized van der Waals heterostructures of MoSe2/WSe2 exhibit strong electronic coupling. Strain engineering of these materials shows tunable band gaps, paving the way for flexible electronics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Vertically stacked van der Waals heterostructures offer unique properties from interlayer interactions.
- Experimental challenges include layer twisting and contamination, obscuring intrinsic electronic coupling.
Purpose of the Study:
- To investigate the electronic structure and strain dependence of directly synthesized MoSe2/WSe2 heterostructures.
- To demonstrate strong electronic coupling in these van der Waals heterostructures.
Main Methods:
- Direct synthesis of MoSe2/WSe2 heterostructures via chemical vapor deposition.
- Photoluminescence spectroscopy to measure band gaps and their response to strain.
Main Results:
- MoSe2/WSe2 heterostructures show reduced direct (1.48 eV) and indirect (1.28 eV) band gaps compared to individual layers.
- Tensile strain induces redshifts in both band gaps, with the indirect gap being more sensitive.
- Strong electronic coupling between MoSe2 and WSe2 layers was confirmed.
Conclusions:
- Direct synthesis overcomes challenges in creating van der Waals heterostructures with strong interlayer coupling.
- Strain engineering provides a method to tune the electronic properties of MoSe2/WSe2 heterostructures.
- This work enables the development of novel flexible electronic devices.
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