Photoluminescence linewidth narrowing of InAs/GaAs self-assembled quantum dots

✍ Scribed by S Kiravittaya; Y Nakamura; O.G Schmidt

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 151 KB
• Volume: 13
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/s1386-9477(01)00525-2

✦ Synopsis

The e ects of desorption and di usion of indium adatoms on the photoluminescence (PL) from InAs self-assembled quantum dots (QDs) are investigated by introducing growth interruptions after QD formation. Large, low-density and small, high-density QDs were grown by molecular beam epitaxy using low (0:01 ML=s) and high (0:2 ML=s) growth rates, respectively. The PL from the QDs grown at 0:01 ML=s and with various growth interruption times exhibit decreasing linewidths from 40 to 32 meV with increasing growth interruption time up to 30 s. The narrowing of the PL linewidth results from improved size homogeneity due to desorption and di usion of adatoms from small (¡ 30 nm) InAs clusters. The narrowing of the PL linewidth from the InAs dots is combined with low-temperature GaAs capping to obtain a linewidth of 26 meV.