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Updated: Jun 26, 2026

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Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Andreev molecules in semiconductor nanowire double quantum dots.
Zhaoen Su1, Alexandre B Tacla2, Moïra Hocevar3,4
1Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, 15260, USA.
Nature Communications
|September 21, 2017
Summary
Researchers coupled superconducting quantum dots in nanowires to create Andreev molecular states. This work is a key step toward building longer chains for topological quantum simulation.
Area of Science:
- Condensed Matter Physics
- Quantum Computing
Background:
- Superconducting quantum dots are promising for realizing topological superconductors.
- Understanding interdot coupling is crucial for controlling longer chains.
Purpose of the Study:
- To investigate the coupling of electronic states in a double quantum dot system.
- To explore the formation of Andreev molecular states as building blocks for quantum simulators.
Main Methods:
- Fabrication of double quantum dots in indium antimonide nanowires using gate voltages.
- Integration of high-transparency superconducting niobium titanium nitride contacts.
- Measurement of electron transport and study of Andreev bound states.
Main Results:
- Demonstrated hybridization of Andreev bound states to form Andreev molecular states.
- Observed evolution of these states with charge parity and magnetic field.
- Experimental results show agreement with a numerical model.
Conclusions:
- Coupled superconducting quantum dots in nanowires can form Andreev molecular states.
- This system serves as a potential building block for solid-state quantum simulators.
- Further development could lead to the realization of the Kitaev model.
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