Autor: |
Shulun Li, Xiangjun Shang, Yao Chen, Xiangbin Su, Huiming Hao, Hanqing Liu, Yu Zhang, Haiqiao Ni, Zhichuan Niu |
Jazyk: |
angličtina |
Rok vydání: |
2021 |
Předmět: |
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Zdroj: |
Nanomaterials, Vol 11, Iss 5, p 1136 (2021) |
Druh dokumentu: |
article |
ISSN: |
2079-4991 |
DOI: |
10.3390/nano11051136 |
Popis: |
Uniform arrays of three shapes (gauss, hat, and peak) of GaAs microlenses (MLs) by wet-etching are demonstrated, ∼200 nm spatial isolation of epitaxial single QDs embedded (λ: 890–990 nm) and broadband (Δλ∼80 nm) enhancement of their quantum light extraction are obtained, which is also suitable for telecom-band epitaxial QDs. Combined with the bottom distributed Bragg reflector, the hat-shaped ML forms a cavity and achieves the best enhancement: extraction efficiency of 26%, Purcell factor of 2 and single-photon count rate of 7×106 counts per second at the first lens; while the gauss-shaped ML shows a broader band (e.g., longer λ) enhancement. In the MLs, single QDs with featured exciton emissions are observed, whose time correlations prove single-photon emission with multi-photon probability g(2)(0)=0.02; some QDs show both biexciton XX and exciton X emissions and exhibit a perfect cascade feature. This work could pave a step towards a scalable array of QD single-photon sources and the application of QD photon-pair emission for entanglement experiments. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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