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Updated: Jun 12, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Correlation-induced conductance suppression at level degeneracy in a quantum dot
H A Nilsson1, O Karlström, M Larsson
1Nanometer Structure Consortium, Lund University, Box 118, 221 00 Lund, Sweden.
Physical Review Letters
|May 21, 2010
Summary
Large g factors in indium antimonide (InSb) nanowire quantum dots reveal unique conductance behaviors. We observed Kondo effect enhancements and a novel conductance suppression for same-spin level alignments, supported by calculations.
Area of Science:
- Condensed matter physics
- Quantum dot physics
- Nanowire electronics
Background:
- Indium antimonide (InSb) nanowires exhibit large, level-dependent g factors, influencing quantum phenomena.
- Quantum dots are crucial for studying electron interactions and quantum effects.
Purpose of the Study:
- Investigate conductance properties in InSb nanowire quantum dots.
- Explore the impact of level alignment and spin on quantum dot behavior.
- Characterize novel conductance suppression and correlation-induced resonances.
Main Methods:
- Fabrication and characterization of InSb nanowire quantum dots.
- Electrical transport measurements at low temperatures.
- Numerical and analytical calculations to support experimental findings.
Main Results:
- Observed standard Kondo effect (conductance enhancement) for aligned, different-spin levels.
- Discovered a novel conductance suppression ('canyon') for aligned, same-spin levels.
- Identified correlation-induced resonance at the center of the Coulomb blockade region.
Conclusions:
- Large g factors in InSb nanowires lead to diverse level crossing phenomena.
- Same-spin level alignment results in unique conductance suppression.
- Experimental results are consistent with theoretical predictions, advancing quantum dot understanding.
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