Publikationsdatum:
2015-02-24
Beschreibung:
Photoluminescence (PL) at wavelengths over 1.55 μ m from self-assembled InAs quantum dots (QDs) grown on GaAs(001) is observed at room temperature (RT) and 4 K using a bilayer structure with thin cap. The PL peak has been known to redshift with decreasing cap layer thickness, although accompanying intensity decrease and peak broadening. With our strain-controlled bilayer structure, the PL intensity can be comparable to the ordinary QDs while realizing peak emission wavelength of 1.61 μ m at 4 K and 1.73 μ m at RT. The key issue lies in the control of strain not only in the QDs but also in the cap layer. By combining with underlying seed QD layer, we realize strain-driven bandgap engineering through control of strain in the QD and cap layers.
Print ISSN:
0003-6951
Digitale ISSN:
1077-3118
Thema:
Physik
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