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Updated: May 1, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
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Unintentional high-density p-type modulation doping of a GaAs/AlAs core-multishell nanowire
J Jadczak1, P Plochocka, A Mitioglu
1Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA , 143, avenue de Rangueil, 31400 Toulouse, France.
Nano Letters
|April 22, 2014
Summary
Achieving controlled p-type doping in gallium arsenide/aluminum arsenide (GaAs/AlAs) core-shell nanowires is now possible. A GaAs quantum well in the AlAs shell captures carbon, enabling unintentional p-type doping and quantum confinement effects.
Area of Science:
- Semiconductor Nanostructures
- Materials Science
- Quantum Physics
Background:
- Doping challenges in gallium arsenide/aluminum arsenide (GaAs/AlAs) core-shell nanowires (NWs) hinder technological applications.
- The amphoteric nature of dopant atoms complicates achieving controlled doping levels.
Purpose of the Study:
- To demonstrate a method for achieving unintentional p-type doping in GaAs/AlAs core-shell NWs.
- To investigate the quantum confinement effects and electronic properties of these doped NWs.
Main Methods:
- Fabrication of GaAs/AlAs core-multishell NWs with an embedded GaAs quantum well.
- Magneto-optical studies, including microphotoluminescence in a high magnetic field.
- Theoretical calculations of the NW electronic structure.
Main Results:
- A narrow GaAs quantum well within the AlAs shell effectively getters carbon acceptors, resulting in unintentional p-type doping.
- Magneto-optical studies revealed quantum-confined emission.
- Electronic structure calculations confirmed carrier confinement at the core/shell interface due to ionized carbon acceptors.
- Microphotoluminescence showed avoided crossings between Landau level emission and phonon replicas, indicating a high 2D hole density.
Conclusions:
- Embedding a GaAs quantum well in AlAs shells is an effective strategy for unintentional p-type doping in NWs.
- The structure exhibits significant quantum confinement and resonant hole-phonon interactions.
- This approach facilitates the study of 2D hole systems in semiconductor nanowires.
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