Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band Alignment
Exciton recombination and spin dynamics in (In,Al)As/AlAs quantum dots (QDs) with indirect band gap and type-I band alignment were studied. The negligible (less than 0.2 μeV) value of the anisotropic exchange interaction in these QDs prevents the mixing of the excitonic basis states and makes the fo...
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| Format: | Article |
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MDPI AG
2023-02-01
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| Series: | Nanomaterials |
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| Online Access: | https://www.mdpi.com/2079-4991/13/4/729 |
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| author | T. S. Shamirzaev A. V. Shumilin D. S. Smirnov D. Kudlacik S. V. Nekrasov Yu G. Kusrayev D. R. Yakovlev M. Bayer |
| author_facet | T. S. Shamirzaev A. V. Shumilin D. S. Smirnov D. Kudlacik S. V. Nekrasov Yu G. Kusrayev D. R. Yakovlev M. Bayer |
| author_sort | T. S. Shamirzaev |
| collection | DOAJ |
| description | Exciton recombination and spin dynamics in (In,Al)As/AlAs quantum dots (QDs) with indirect band gap and type-I band alignment were studied. The negligible (less than 0.2 μeV) value of the anisotropic exchange interaction in these QDs prevents the mixing of the excitonic basis states and makes the formation of spin-polarized bright excitons possible under quasi-resonant, circularly polarized excitation. The recombination and spin dynamics of excitons are controlled by the hyperfine interaction between the electron and nuclear spins. A QD blockade by dark excitons was observed in the magnetic field, that eliminates the impact of nuclear spin fluctuations. A kinetic model which accounts for the population dynamics of the bright and dark exciton states as well as for the spin dynamics was developed to quantitatively describe the experimental data. |
| first_indexed | 2024-03-11T08:19:30Z |
| format | Article |
| id | doaj.art-02af293655664ed2ad611498f108b259 |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-03-11T08:19:30Z |
| publishDate | 2023-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Nanomaterials |
| spelling | doaj.art-02af293655664ed2ad611498f108b2592023-11-16T22:28:07ZengMDPI AGNanomaterials2079-49912023-02-0113472910.3390/nano13040729Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band AlignmentT. S. Shamirzaev0A. V. Shumilin1D. S. Smirnov2D. Kudlacik3S. V. Nekrasov4Yu G. Kusrayev5D. R. Yakovlev6M. Bayer7Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, RussiaIoffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, RussiaIoffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, RussiaExperimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, GermanyIoffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, RussiaIoffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, RussiaIoffe Institute, Russian Academy of Sciences, 194021 St. Petersburg, RussiaExperimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, GermanyExciton recombination and spin dynamics in (In,Al)As/AlAs quantum dots (QDs) with indirect band gap and type-I band alignment were studied. The negligible (less than 0.2 μeV) value of the anisotropic exchange interaction in these QDs prevents the mixing of the excitonic basis states and makes the formation of spin-polarized bright excitons possible under quasi-resonant, circularly polarized excitation. The recombination and spin dynamics of excitons are controlled by the hyperfine interaction between the electron and nuclear spins. A QD blockade by dark excitons was observed in the magnetic field, that eliminates the impact of nuclear spin fluctuations. A kinetic model which accounts for the population dynamics of the bright and dark exciton states as well as for the spin dynamics was developed to quantitatively describe the experimental data.https://www.mdpi.com/2079-4991/13/4/729quantum dotsexcitonsspinsoptical orientationhyperfine interactionspin blockade |
| spellingShingle | T. S. Shamirzaev A. V. Shumilin D. S. Smirnov D. Kudlacik S. V. Nekrasov Yu G. Kusrayev D. R. Yakovlev M. Bayer Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band Alignment Nanomaterials quantum dots excitons spins optical orientation hyperfine interaction spin blockade |
| title | Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band Alignment |
| title_full | Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band Alignment |
| title_fullStr | Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band Alignment |
| title_full_unstemmed | Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band Alignment |
| title_short | Optical Orientation of Excitons in a Longitudinal Magnetic Field in Indirect-Band-Gap (In,Al)As/AlAs Quantum Dots with Type-I Band Alignment |
| title_sort | optical orientation of excitons in a longitudinal magnetic field in indirect band gap in al as alas quantum dots with type i band alignment |
| topic | quantum dots excitons spins optical orientation hyperfine interaction spin blockade |
| url | https://www.mdpi.com/2079-4991/13/4/729 |
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