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Updated: May 20, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Electrostatic spin control in InAs/InP nanowire quantum dots.
Lorenzo Romeo1, Stefano Roddaro, Alessandro Pitanti
1NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, I-56127 Pisa, Italy.
Nano Letters
|August 2, 2012
Summary
Robust voltage-controlled spin transitions in few-electron quantum dots were observed. Anomalous spin configurations in indium arsenide/indium phosphide nanowires are visible even above 20 K.
Area of Science:
- Quantum physics
- Condensed matter physics
- Nanotechnology
Background:
- Few-electron quantum dots are crucial for quantum computing.
- Understanding spin transitions is key to controlling quantum states.
Purpose of the Study:
- To demonstrate robust voltage-controlled spin transitions in few-electron quantum dots.
- To investigate spin filling schemes and transitions in confined systems.
Main Methods:
- Utilized lateral-gate electrodes on an InAs/InP nanowire to apply electric fields.
- Performed transport measurements to probe spin states and energy levels.
Main Results:
- Demonstrated breakdown of the standard spin filling scheme, showing singlet-triplet transitions.
- Observed anomalous spin configurations with energy gain exceeding 4 meV.
- Confirmed visibility of these transitions at temperatures above 20 K.
Conclusions:
- Strong confinement in quantum dots enables robust, voltage-controlled spin transitions.
- Anomalous spin configurations are energetically favorable and observable at higher temperatures.
- These findings advance the control of quantum states in nanodevices.
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