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Updated: Jan 12, 2026
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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
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Interfacial excitons across dimensional boundaries: a mixed-dimensional SnS/BNNT heterostructure
Dhanjit Talukdar1, Dambarudhar Mohanta2, Gazi A Ahmed1
1Optoelectronics and Photonics Laboratory, Department of Physics, Tezpur University, Napaam 784028, Assam, India. talukdardhanjit123@gmail.com.
Nanoscale
|October 31, 2025
Summary
We discovered interdimensional excitons (IDEs) in a mixed-dimensional heterostructure of SnS and Boron Nitride Nanotubes (BNNTs). This finding opens new avenues for anisotropic optoelectronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Interfacial excitons are typically observed in 2D van der Waals (vdW) heterostructures.
- Excitonic behavior in mixed-dimensional systems is not well understood.
Purpose of the Study:
- To investigate the formation and properties of excitons in mixed-dimensional heterostructures.
- To explore the potential of SnS/BNNT heterostructures for novel optoelectronic applications.
Main Methods:
- Utilized many-body perturbation theory within the GW approximation and Bethe-Salpeter equation (GW + BSE).
- Simulated a mixed-dimensional heterostructure (MDH) composed of SnS and Boron Nitride Nanotubes (BNNTs).
Main Results:
- Demonstrated the formation of an interdimensional exciton (IDE) in the SnS/BNNT MDH.
- Observed an electron transition from the 2D valence band of SnS to the 1D conduction band of BNNT.
- Identified highly anisotropic, direction-dependent exciton effective mass due to quantum confinement in the BNNT.
Conclusions:
- Established a theoretical framework for understanding excitons in mixed-dimensional vdW heterostructures.
- Highlighted the potential of these systems for developing anisotropic optoelectronic devices.
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