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Updated: May 30, 2026
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Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Spin-polarized transport through an Aharonov-Bohm interferometer embedded with a quantum dot molecule
Yibo Ying1, Guojun Jin, Yu-Qiang Ma
1National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, 210093, People's Republic of China.
Summary
We demonstrate a novel Aharonov-Bohm interferometer controlling electron spin transport. This device utilizes Fano and Rashba effects for tunable spin polarization and spin accumulation in quantum dots.
Area of Science:
- Quantum physics
- Condensed matter physics
- Nanotechnology
Background:
- Aharonov-Bohm interferometers probe quantum phenomena.
- Quantum dot molecules offer tunable electronic properties.
- Fano and Rashba effects influence electron transport and spin.
Purpose of the Study:
- Investigate spin-dependent transport in a quantum dot molecule interferometer.
- Explore the interplay of Fano and Rashba effects on conductance.
- Analyze control over spin polarization and accumulation.
Main Methods:
- Theoretical modeling of an Aharonov-Bohm interferometer.
- Inclusion of a quantum dot molecule in one arm.
- Analysis of Fano resonances and Rashba spin-orbit interaction.
Main Results:
- Observed opposite asymmetric tails in Fano resonances.
- Rashba spin-orbit interaction induces spin-dependent phase shifts.
- Achieved overlapping Fano dips/peaks for specific spin components.
- Demonstrated control over spin polarization via Rashba parameter and interdot coupling.
- Generated opposite sign spin accumulations in quantum dots.
Conclusions:
- The proposed interferometer enables manipulation of spin transport.
- Tunable spin polarization and accumulation are achievable.
- Interplay of Fano and Rashba effects is crucial for spin control.
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