Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum Dots
Semiconductor self-assembled quantum dots (QDs) have garnered immense attention for their potential in various quantum technologies and photonics applications. Here, we explore a novel approach for fine-tuning the emission wavelength of QDs by building upon the indium flush growth method: Submonolay...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-11-01
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| Series: | Crystals |
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| Online Access: | https://www.mdpi.com/2073-4352/13/12/1657 |
| _version_ | 1797381442593882112 |
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| author | Nikolai Spitzer Nikolai Bart Hans-Georg Babin Marcel Schmidt Andreas D. Wieck Arne Ludwig |
| author_facet | Nikolai Spitzer Nikolai Bart Hans-Georg Babin Marcel Schmidt Andreas D. Wieck Arne Ludwig |
| author_sort | Nikolai Spitzer |
| collection | DOAJ |
| description | Semiconductor self-assembled quantum dots (QDs) have garnered immense attention for their potential in various quantum technologies and photonics applications. Here, we explore a novel approach for fine-tuning the emission wavelength of QDs by building upon the indium flush growth method: Submonolayer variations in the capping thickness reveal a non-monotonic progression, where the emission energy can decrease even though the capping thickness decreases. indium flush, a well-known technique for inducing blue shifts in quantum dot emissions, involves the partial capping of QDs with GaAs followed by a temperature ramp-up. However, our findings reveal that the capping layer roughness, stemming from fractional monolayers during overgrowth, plays a pivotal role in modulating the emission energy of these QDs. We propose increased indium interdiffusion between the QDs and the surrounding GaAs capping layer for a rough surface surrounding the QD as the driving mechanism. This interdiffusion alters the indium content within the QDs, resulting in an additional emission energy shift, counterintuitive to the capping layer’s thickness increase. We utilize photoluminescence spectroscopy to generate wafer maps depicting the emission spectrum of the QDs. Using thickness gradients, we produce systematic variations in the capping layer thickness on 3″ wafers, resulting in modulations of the emission energy of up to 26 meV. |
| first_indexed | 2024-03-08T20:52:34Z |
| format | Article |
| id | doaj.art-3d3e3fa7371d4408ad7620e865a5de62 |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-03-08T20:52:34Z |
| publishDate | 2023-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Crystals |
| spelling | doaj.art-3d3e3fa7371d4408ad7620e865a5de622023-12-22T14:01:54ZengMDPI AGCrystals2073-43522023-11-011312165710.3390/cryst13121657Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum DotsNikolai Spitzer0Nikolai Bart1Hans-Georg Babin2Marcel Schmidt3Andreas D. Wieck4Arne Ludwig5Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, GermanyLehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, GermanyLehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, GermanyLehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, GermanyLehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, GermanyLehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, GermanySemiconductor self-assembled quantum dots (QDs) have garnered immense attention for their potential in various quantum technologies and photonics applications. Here, we explore a novel approach for fine-tuning the emission wavelength of QDs by building upon the indium flush growth method: Submonolayer variations in the capping thickness reveal a non-monotonic progression, where the emission energy can decrease even though the capping thickness decreases. indium flush, a well-known technique for inducing blue shifts in quantum dot emissions, involves the partial capping of QDs with GaAs followed by a temperature ramp-up. However, our findings reveal that the capping layer roughness, stemming from fractional monolayers during overgrowth, plays a pivotal role in modulating the emission energy of these QDs. We propose increased indium interdiffusion between the QDs and the surrounding GaAs capping layer for a rough surface surrounding the QD as the driving mechanism. This interdiffusion alters the indium content within the QDs, resulting in an additional emission energy shift, counterintuitive to the capping layer’s thickness increase. We utilize photoluminescence spectroscopy to generate wafer maps depicting the emission spectrum of the QDs. Using thickness gradients, we produce systematic variations in the capping layer thickness on 3″ wafers, resulting in modulations of the emission energy of up to 26 meV.https://www.mdpi.com/2073-4352/13/12/1657molecular beam epitaxyquantum dotsindium flush method |
| spellingShingle | Nikolai Spitzer Nikolai Bart Hans-Georg Babin Marcel Schmidt Andreas D. Wieck Arne Ludwig Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum Dots Crystals molecular beam epitaxy quantum dots indium flush method |
| title | Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum Dots |
| title_full | Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum Dots |
| title_fullStr | Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum Dots |
| title_full_unstemmed | Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum Dots |
| title_short | Wafer-Scale Emission Energy Modulation of Indium Flushed Quantum Dots |
| title_sort | wafer scale emission energy modulation of indium flushed quantum dots |
| topic | molecular beam epitaxy quantum dots indium flush method |
| url | https://www.mdpi.com/2073-4352/13/12/1657 |
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