| Alternative title | Direct-gap photoluminescence from a Si-Ge multilayer super unit cell grown on Si0.4 Ge 0.6 |
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| Download | - View final version: Direct-gap photoluminescence from a Si-Ge multilayer super unit cell grown on Si₀.₄ Ge₀.₆ (PDF, 1014 KiB)
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| DOI | Resolve DOI: https://doi.org/10.1149/2.0231808jss |
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| Author | Search for: Lockwood, D. J.1; Search for: Rowell, N. L.1; Search for: Favre, L.; Search for: Ronda, A.; Search for: Berbezier, I. |
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| Affiliation | - National Research Council of Canada. Measurement Science and Standards
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| Format | Text, Article |
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| Conference | Meeting of the Electrochemical Society, May 11-15, 2014, Orlando, Florida |
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| Subject | germanium; luminescence; silicon |
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| Abstract | Both Si and Ge possess indirect band gaps, which makes them very inefficient light emitters. One way to overcome this limitationis through bandgap engineering. M. d'Avezac et al. predicted in 2012 that a strained SiGe₂Si₂Ge₂SiGeₙ super unit cell on Si₀.₄ Ge₀.₆ would have a direct and dipole-allowed gap of 0.863 eV, which is suited for optical fiber applications. Here we report onthe epitaxial growth of such a structure and its optical properties, for which purpose two similar samples were prepared bymolecular beam epitaxy and solid phase epitaxy. Photoluminescence (PL) spectra were obtained at low temperatures (6–25 K)with excitation at wavelengths of 405 and 458 nm, which emphasize the light emission from the sample superstructure. A stronglow-energy PL quadruplet is seen, with peaks near 727, 758, 792 and 822 meV at 6 K, together with a much weaker peak at 871meV. The ratio of intensities of the strong and weak peaks is the same in both samples. The weak peak at 871 meV is assignedto the dipole-allowed direct-gap transition associated with the super unit cell. The four strong peaks are attributed to dislocationrelated emission lines of the thick relaxed Si₀.₄ Ge₀.₆ transition layer. |
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| Publication date | 2018-07-28 |
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| Publisher | The Electrochemical Society |
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| In | |
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| Language | English |
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| Peer reviewed | Yes |
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| Export citation | Export as RIS |
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| Report a correction | Report a correction (opens in a new tab) |
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| Record identifier | 58225a6c-31fc-4342-a728-1a0d702c34f4 |
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| Record created | 2020-01-29 |
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| Record modified | 2020-05-30 |
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