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Coherent coupling of two quantum dots embedded in an Aharonov-Bohm interferometer
A W Holleitner1, C R Decker, H Qin
1Center for NanoScience and Sektion Physik, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany. Alex.Holleitner@physik.uni-muenchen.de
Physical Review Letters
|December 12, 2001
Summary
Researchers studied coupled quantum dots, observing Aharonov-Bohm oscillations and molecular states. They analyzed how magnetic fields affect coherently coupled states in these small electron systems.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Nanotechnology
Background:
- Quantum dots are semiconductor nanocrystals with tunable electronic properties.
- The Aharonov-Bohm effect demonstrates the wave nature of charged particles influenced by magnetic fields.
- Understanding coupled quantum dot systems is crucial for quantum computing and electronics.
Purpose of the Study:
- To investigate the electronic properties of two coupled quantum dots.
- To explore the Aharonov-Bohm oscillations in a tunable coupling regime.
- To analyze molecular states and their magnetic field dependence in a double quantum dot system.
Main Methods:
- Fabrication of two laterally gated quantum dots with fewer than 15 electrons.
- Experimental setup in an Aharonov-Bohm geometry allowing variable inter-dot coupling.
- Measurement of Aharonov-Bohm oscillations and characterization of molecular states.
Main Results:
- Observed distinct Aharonov-Bohm oscillations in the weakly coupled regime.
- Identified and studied molecular states in the intermediate coupling regime.
- Extracted the magnetic field dependence of coherently coupled states.
Conclusions:
- The study demonstrates control over coupling in double quantum dots.
- Aharonov-Bohm oscillations provide insights into quantum interference effects.
- The findings contribute to the understanding of quantum phenomena in artificial molecules.
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