Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom range
We demonstrate a new quantum-confined semiconductor material based on GaSb quantum dots (QDs) embedded in a single-crystalline AlGaSb matrix by filling droplet-etched nanoholes. The droplet-mediated growth mechanism allows formation of low QD densities required for non-classical single-QD light sour...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
AIP Publishing LLC
2021-05-01
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| Series: | APL Materials |
| Online Access: | http://dx.doi.org/10.1063/5.0049788 |
| _version_ | 1818730703893823488 |
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| author | Abhiroop Chellu Joonas Hilska Jussi-Pekka Penttinen Teemu Hakkarainen |
| author_facet | Abhiroop Chellu Joonas Hilska Jussi-Pekka Penttinen Teemu Hakkarainen |
| author_sort | Abhiroop Chellu |
| collection | DOAJ |
| description | We demonstrate a new quantum-confined semiconductor material based on GaSb quantum dots (QDs) embedded in a single-crystalline AlGaSb matrix by filling droplet-etched nanoholes. The droplet-mediated growth mechanism allows formation of low QD densities required for non-classical single-QD light sources. The photoluminescence (PL) experiments reveal that the GaSb QDs have an indirect–direct bandgap crossover at telecom wavelengths. This is due to the alignment of the Γ and L valleys in the conduction band as a result of the quantum confinement controlled by the dimensions of the nanostructure. We show that in the direct bandgap regime close to 1.5 µm wavelength, the GaSb QDs have a type I band alignment and exhibit excitonic emission with narrow spectral lines and very low inhomogeneous broadening of PL emission owing to the high material quality and dimensional uniformity. These properties are extremely promising in terms of applications in infrared quantum optics and quantum photonic integration. |
| first_indexed | 2024-12-17T23:06:00Z |
| format | Article |
| id | doaj.art-ec1456cca4c54a518bc73ee27016d219 |
| institution | Directory Open Access Journal |
| issn | 2166-532X |
| language | English |
| last_indexed | 2024-12-17T23:06:00Z |
| publishDate | 2021-05-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | APL Materials |
| spelling | doaj.art-ec1456cca4c54a518bc73ee27016d2192022-12-21T21:29:16ZengAIP Publishing LLCAPL Materials2166-532X2021-05-0195051116051116-710.1063/5.0049788Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom rangeAbhiroop Chellu0Joonas Hilska1Jussi-Pekka Penttinen2Teemu Hakkarainen3Optoelectronics Research Centre, Physics Unit, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, FinlandOptoelectronics Research Centre, Physics Unit, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, FinlandOptoelectronics Research Centre, Physics Unit, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, FinlandOptoelectronics Research Centre, Physics Unit, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, FinlandWe demonstrate a new quantum-confined semiconductor material based on GaSb quantum dots (QDs) embedded in a single-crystalline AlGaSb matrix by filling droplet-etched nanoholes. The droplet-mediated growth mechanism allows formation of low QD densities required for non-classical single-QD light sources. The photoluminescence (PL) experiments reveal that the GaSb QDs have an indirect–direct bandgap crossover at telecom wavelengths. This is due to the alignment of the Γ and L valleys in the conduction band as a result of the quantum confinement controlled by the dimensions of the nanostructure. We show that in the direct bandgap regime close to 1.5 µm wavelength, the GaSb QDs have a type I band alignment and exhibit excitonic emission with narrow spectral lines and very low inhomogeneous broadening of PL emission owing to the high material quality and dimensional uniformity. These properties are extremely promising in terms of applications in infrared quantum optics and quantum photonic integration.http://dx.doi.org/10.1063/5.0049788 |
| spellingShingle | Abhiroop Chellu Joonas Hilska Jussi-Pekka Penttinen Teemu Hakkarainen Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom range APL Materials |
| title | Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom range |
| title_full | Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom range |
| title_fullStr | Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom range |
| title_full_unstemmed | Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom range |
| title_short | Highly uniform GaSb quantum dots with indirect–direct bandgap crossover at telecom range |
| title_sort | highly uniform gasb quantum dots with indirect direct bandgap crossover at telecom range |
| url | http://dx.doi.org/10.1063/5.0049788 |
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