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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Spin transport of excitons
J R Leonard1, Y Y Kuznetsova, Sen Yang
1Department of Physics, University of California at San Diego, La Jolla, California 92093-0319, USA. jleonard@physics.ucsd.edu
Nano Letters
|September 29, 2009
Summary
We observed spin transport of spatially indirect excitons over micrometers in coupled quantum wells. This is due to significantly enhanced exciton spin relaxation times compared to conventional quantum wells.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Semiconductor spintronics
Background:
- Spatially indirect excitons are crucial for quantum information processing.
- Exciton spin relaxation limits their transport distance in conventional quantum wells.
Purpose of the Study:
- To investigate the spin transport of spatially indirect excitons in GaAs/AlGaAs coupled quantum wells (CQW).
- To understand the factors enabling long-distance exciton spin transport.
Main Methods:
- Fabrication and characterization of GaAs/AlGaAs coupled quantum wells.
- Measurement of exciton spin transport dynamics.
- Analysis of exciton spin relaxation times.
Main Results:
- Demonstrated spin transport of spatially indirect excitons over distances up to several micrometers.
- Observed orders of magnitude enhancement in exciton spin relaxation time in CQW compared to conventional quantum wells.
Conclusions:
- Coupled quantum wells significantly enhance exciton spin relaxation times, enabling long-distance spin transport.
- Spatially indirect excitons in CQW are promising for future spintronic applications.
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