| 1. |
- Wu, Xiaoyan, et al.
(författare)
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Anomalous photoluminescence in InP1-xBix
- 2016
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 6, s. Art. no. 27867-
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Tidskriftsartikel (refereegranskat)abstract
- Low temperature photoluminescence (PL) from InP1-xBix thin films with Bi concentrations in the 0-2.49% range reveals anomalous spectral features with strong and very broad (linewidth of 700 nm) PL signals compared to other bismide alloys. Multiple transitions are observed and their energy levels are found much smaller than the band-gap measured from absorption measurements. These transitions are related to deep levels confirmed by deep level transient spectroscopy, which effectively trap free holes and enhance radiative recombination. The broad luminescence feature is beneficial for making super-luminescence diodes, which can theoretically enhance spatial resolution beyond 1 ?m in optical coherent tomography (OCT).
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| 2. |
- Pan, Wenwu, et al.
(författare)
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Photoluminescence of InGaAs/GaAsBi/InGaAs type-II quantum wells grown by gas source molecular beam epitaxy
- 2017
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Ingår i: Semiconductor Science and Technology. - : IOP Publishing. - 1361-6641 .- 0268-1242. ; 32:1
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Tidskriftsartikel (refereegranskat)abstract
- InxGa1-xAs/GaAs1-yBiy/InxGa1-xAs (0.20 ≤x ≤0.22, 0.035 ≤y ≤0.045) quantum wells (QWs) were grown on GaAs substrates by gas source molecular beam epitaxy for realizing the type-II band edge line-up. Both type-I and type-II transitions were observed in the Bi containing W QWs and the photoluminescence intensity was enhanced in the sample with a high Bi content, which is mainly due to the improvement of carrier confinement. The 8 band k • p model was used to analyze the electronic properties in the QWs and the calculated transition energies fit well with the experiment results. Our study shows that the proposed type-II QW is a promising candidate for realizing GaAs-based near infrared light emitting devices near 1.3 μm
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| 3. |
- Liu, Juanjuan, et al.
(författare)
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Electrically injected GaAsBi/GaAs single quantum well laser diodes
- 2017
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Ingår i: AIP Advances. - : AIP Publishing. - 2158-3226 .- 2158-3226. ; 7:11, s. Article Number: 115006 -
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Tidskriftsartikel (refereegranskat)abstract
- We present electrically injected GaAs/GaAsBi single quantum well laser diodes (LDs) emitting at a record long wavelength of 1141 nm at room temperature grown by molecular beam epitaxy. The LDs have excellent device performances with internal quantum efficiency of 86%, internal loss of 10 cm-1 and transparency current density of 196 A/cm2. The LDs can operate under continuous-wave mode up to 273 K. The characteristic temperature are extracted to be 125 K in the temperature range of 77?150 K, and reduced to 90 K in the range of 150?273 K. The temperature coefficient of 0.3 nm/K is extracted in the temperature range of 77?273 K.
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| 4. |
- Wang, Shu Min, 1963, et al.
(författare)
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Novel Dilute Bismides for IR Optoelectronics Applications
- 2013
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Ingår i: Asia Communications and Photonics Conference, ACP. - Washington, D.C. : OSA. - 2162-108X.
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Konferensbidrag (refereegranskat)abstract
- III-V-Bi compounds reveal a number of attractive physical properties promising for novel IR optoelectronic applications [1,2] and have received considerable attention as witnessed by the dedicated international workshops on this topic in the consecutive past four years. The isoelectronic nature of Bi atoms in III-Vs induces strong interactions with the energy bands of host materials leading to large band-gap reduction, less temperature sensitive band-gap and large spin-orbit split band. So far the most studied material is Ga(N)AsBi, while other dilute bismides have also been reported recently. In this paper, we shall briefly review several novel bismides: GaSbBi, InSbiBi, InAsBi, InPBi and InGaAsBi, and the Bi surfactant effect from our group, all grown by molecular beam epitaxy (MBE).
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| 5. |
- Han, Yi, et al.
(författare)
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Abnormal strain in suspended GeSn microstructures
- 2018
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Ingår i: Materials Research Express. - : IOP Publishing. - 2053-1591. ; 5:3
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Tidskriftsartikel (refereegranskat)abstract
- A suspended GeSn microstructure is realized by a two-step selective wet etching technique with the aim of fully relaxing the compressive strain, promoting the indirect to direct bandgap transition and improving the optical property of GeSn thin films grown on Ge. The compressive strain was found efficiently relaxed, and even unexpected large tensile strain was displayed on regions of the microstructure by micro-Raman spectroscopy. Residual Ge patches under the suspended GeSn microstructure were found by scanning electron microscopy and proved to be the origin of the tensile strain by finite element method simulations. The tensile strain on the surface is beneficial for direct bandgap conversion and carrier accumulation. Significant enhancement of photoluminescence was obtained in the GeSn microstructures than the original thin film.
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| 6. |
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| 7. |
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| 8. |
- Wang, Shu Min, 1963, et al.
(författare)
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Electrically pumped GaAsBi laser diodes
- 2017
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Ingår i: International Conference on Transparent Optical Networks. - 2162-7339. - 9781538608586
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Konferensbidrag (refereegranskat)abstract
- In this paper, we present electrically pumped GaAsBi quantum well (QW) laser diodes (LDs) grown by molecular beam epitaxy. The LDs reveal a record long lasing wavelength of 1.14 μm at 300 K and can be operated under CW excitation up to 273 K. They also show high performance with an internal quantum efficiency of 86% and an internal optical loss of 10 cm-1. The characteristic temperature is 79 K in the temperature range of 225-350 K and the temperature coefficient of the lasing wavelength is 0.26 nm/K at 77 - 350 K, much smaller than 0.35 - 0.40 nm/K for InGaAs and InGaAsP QW LDs. These results suggest that GaAsBi LDs are attractive candidates for uncooled near infrared lasers on GaAs.
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| 9. |
- Wang, Shu Min, 1963, et al.
(författare)
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Light emitting devices of dilute bismides
- 2017
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Ingår i: 8th International Workshop on Bi-containing Semiconductors, Marburg, Germany, July 23-26, 2017 (invited talk).
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Konferensbidrag (refereegranskat)
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| 10. |
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