Scattering of two-dimensional electrons by self-assembled InAlAs anti-dots in novel n-AlGaAs/GaAs heterojunctions

✍ Scribed by Takuya Kawazu; Hiroyuki Sakaki

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 270 KB
• Volume: 40
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/j.physe.2007.06.004

✦ Synopsis

Transport properties of a two-dimensional electron gas (2DEG) have been investigated in a novel selectively doped n-AlGaAs/GaAs heterojunction where InAlAs anti-dots are embedded in the vicinity of its channel. Electron mobilities and Shubnikov de Haas oscillations were measured and analyzed to determine the transport lifetime t t and quantum lifetime t q of the 2DEG. It is found that the ratio t t /t q is in the range of 3.5-5, which suggests that the dominant scattering mechanism has a character that is intermediate between an impurity scattering and a surface roughness scattering. Measured data are compared with a theoretical model and well explained by assuming that anti-dots give rise to a potential fluctuation with Gaussian-type correlation originating from the band off set at the dotmatrix boundary.