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Updated: Jan 21, 2026
13:56
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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Nanoscale mapping of quasiparticle band alignment
Søren Ulstrup1, Cristina E Giusca2, Jill A Miwa3
1Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, 8000, Aarhus C, Denmark. ulstrup@phys.au.dk.
Nature Communications
|July 25, 2019
Summary
Researchers mapped electronic band alignments in tungsten disulfide (WS2) using nanoARPES. They found WS2 band offsets correlated with the work function of underlying graphene, influencing luminescence patterns.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Controlling atomic-scale interfaces is vital for electronic devices.
- Two-dimensional materials offer tunable electronic structures via local gating.
- Graphene and tungsten disulfide (WS2) are key 2D materials.
Purpose of the Study:
- Investigate lateral electronic structure variations in WS2.
- Understand how underlying graphene influences WS2 electronic properties.
- Correlate electronic band alignment with luminescence.
Main Methods:
- Utilized single layer and bilayer graphene on silicon carbide.
- Employed angle-resolved photoemission spectroscopy (ARPES) with nano-scale spatial resolution (nanoARPES).
- Mapped electronic band alignments in energy and momentum space.
Main Results:
- WS2 band offsets directly tracked the work function of the underlying graphene.
- Lateral variations in WS2 electronic structure were observed.
- Observed lateral luminescence patterns of excitons and trions in WS2.
Conclusions:
- The work function of graphene dictates the electronic band alignment of adjacent WS2.
- NanoARPES is effective for mapping nanoscale electronic variations.
- Interface engineering of 2D materials can be controlled by substrate properties.
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