Browsing by Author "Wang, H. Y."

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Ion beam studies of InAs/GaAs quantum dots after annealing
(2008-04-01)
Niu, H.
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Chen, C. H.
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Wang, H. Y.
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Wu, S. C.
;
Lee, C. P.
The microstructure changes of self-assembled InAs/GaAs quantum dots during RTA treatment was investigated using ion channeling and photoluminescence (PL). A small blueshift of the PL emission is observed for annealing temperatures of 650-800 degrees C and an obvious blueshift at 850 degrees C. The yield of channeled spectra decreased as annealing temperature was increased, but the yield increased while temperature above 800 degrees C in RTA. These results imply the strain of QD varied during RTA treatments. In addition, the As/Ga atomic ratio near the surface was determined from the surface peaks of the channeled spectrum. (c) 2008 Elsevier B.V. All rights reserved.
The strain status of the buried self-assembled InAs quantum dots using MeV technique
(2006)
Wang, H. Y.
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Chen, C. H.
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Niu, H.
;
Wu, S. C.
;
Lee, C. P.
The strain status of the buried self-assembled InAs quantum dots was comprehended by measurement first time. Results show the in-plane strain is compressive and the lattice in the growth direction is lager than the lattice of GaAs. The strain of the sample annealed at 650 degrees C relaxes in the growth direction. The growth and the lateral direction become relaxed in the sample annealed at 750 degrees C.
Wavelength switching based on quantum-dot vertical-cavity surface-emitting laser
(2012-09-01)
Peng, P. C.
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Wang, H. Y.
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Lan, R. L.
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Lu, H. H.
;
Lin, G. R.
This study investigates, for the first time, static and dynamic wavelength switching characteristics of the 1.3 mu m quantum-dot vertical-cavity surface-emitting laser (QD VCSEL). The free-running QD VCSEL with lambda 1 and lambda 2 state innately is injected by a laser source with lambda 1 state. When the injection power exceeds the threshold power, the dominant state of the QD VCSEL changes from lambda 2 to lambda 1 state. Results of this study demonstrate that the wavelength switching based on a 1.3 mu m QD VCSEL has a simpler and more cost-effective configuration than those of previous systems.