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Updated: Nov 16, 2025
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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
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Band Structure Extraction at Hybrid Narrow-Gap Semiconductor-Metal Interfaces
Sergej Schuwalow1, Niels B M Schröter2, Jan Gukelberger3
1Center for Quantum Devices Niels Bohr Institute University of Copenhagen and Microsoft Quantum Materials Lab Copenhagen Lyngby Denmark.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|March 1, 2021
Summary
This study introduces a method to measure interfacial electronic band structure in quantum devices. This technique helps engineer semiconductor-metal interfaces crucial for topological qubits.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Quantum Computing
Background:
- Accurate interfacial electronic band structure is vital for designing semiconductor-superconductor and semiconductor-metal quantum devices.
- Predicting and measuring band alignment at buried interfaces presents significant theoretical and experimental challenges.
Purpose of the Study:
- To present a reliable procedure for determining critical parameters at semiconductor-metal interfaces.
- To enable precise engineering of quantum devices by understanding band offset, band bending, and accumulation layer subbands.
Main Methods:
- Utilized soft X-ray angle-resolved photoemission spectroscopy.
- Directly measured quantum well states, valence bands, and core levels at the InAs(100)/Al interface.
Main Results:
- Demonstrated that fabrication processes significantly impact band offset at InAs(100)/Al interfaces.
- Showcased how band offset variations influence topological phase diagrams.
Conclusions:
- The developed method reliably determines key parameters for engineering quantum devices.
- This technique is transferable to other narrow-gap semiconductors, facilitating the design of gate-tunable superconducting devices.
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