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Updated: Jun 25, 2026
12:57
Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Antibonding ground states in InAs quantum-dot molecules
M F Doty1, J I Climente, M Korkusinski
1Naval Research Laboratory, Washington, DC 20375, USA. doty@udel.edu
Physical Review Letters
|March 5, 2009
Summary
Coherent tunneling in InAs quantum dots creates molecular states. Barrier thickness dictates whether the ground state is bonding or antibonding, explained by spin-orbit interaction.
Area of Science:
- Quantum physics
- Condensed matter physics
- Materials science
Background:
- Quantum dots exhibit unique electronic properties due to quantum confinement.
- Coherent tunneling allows for the formation of delocalized molecular states between adjacent quantum dots.
Purpose of the Study:
- Investigate the nature of molecular states formed by coherent tunneling between InAs quantum dots.
- Determine the influence of barrier thickness on the orbital character of these molecular states.
- Explain the underlying physical mechanisms, including spin-orbit interaction, driving observed phenomena.
Main Methods:
- Magnetophotoluminescence spectroscopy was employed to probe the electronic states.
- Theoretical analysis utilized a four-band k.p model.
- Atomistic calculations incorporating strain effects were performed.
Main Results:
- Coherent tunneling between InAs quantum dots leads to delocalized molecular states.
- A thin barrier results in a bonding orbital character for the lowest energy molecular state.
- Increased barrier thickness causes a transition to an antibonding orbital character for the ground state.
Conclusions:
- The study confirms theoretical predictions regarding the evolution of molecular state character with barrier thickness.
- Spin-orbit interaction is identified as the key mechanism responsible for the counterintuitive reversal of orbital character.
- The findings provide insights into controlling quantum states in coupled quantum dot systems.
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