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Updated: Jul 18, 2026
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Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Electrically tunable g factors in quantum dot molecular spin states.
M F Doty1, M Scheibner, I V Ponomarev
1Naval Research Laboratory, Washington, D.C. 20375, USA. doty@bloch.nrl.navy.mil
Physical Review Letters
|December 13, 2006
Summary
We studied coupled quantum dots using magnetophotoluminescence. Applying an electric field altered electron spin g factors by tuning molecular orbital wave functions, revealing new control mechanisms.
Area of Science:
- Condensed matter physics
- Quantum dot research
- Semiconductor nanostructures
Background:
- Vertically stacked InAs/GaAs quantum dots offer unique electronic properties.
- Understanding spin behavior in coupled quantum dots is crucial for spintronics.
- Tunnel barriers enable control over inter-dot coupling.
Purpose of the Study:
- Investigate the influence of electric fields on g factors in coupled quantum dots.
- Analyze the role of molecular wave function distribution.
- Develop a model to explain observed g factor changes.
Main Methods:
- Magnetophotoluminescence spectroscopy on individual quantum dot pairs.
- Application of external electric fields to tune inter-dot energy levels.
- Analysis of spin-dependent optical transitions.
Main Results:
- Observed significant resonant changes in g factors with applied electric fields.
- Demonstrated tuning of g factors for spin states with delocalized wave functions.
- Identified distinct g factor behavior for bonding and antibonding states.
Conclusions:
- Electric field control of g factors in coupled quantum dots is feasible.
- Wave function delocalization and orbital formation are key to g factor modulation.
- The proposed model provides insight into spin physics in nanostructures.
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