Low temperature electron mobility in a coupled quantum well system

✍ Scribed by T. Sahu; J. Patnaik

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 129 KB
• Volume: 30
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.2001.0997

✦ Synopsis

We study low temperature electron mobility µ n in a GaAs/Al x Ga 1-x As coupled double quantum well structure. Both the extreme barriers are δ-doped with Si so that the electrons diffuse into the adjacent wells forming two sheets of two-dimensional electron gas (2DEG) separated by a thin central barrier. The subband electron wavefunctions and energy levels are numerically obtained as a function of the well width, barrier width and doping concentration. The screening of ionized impurity potential by the 2D-electrons is obtained in terms of the static dielectric response function within the random phase approximation (RPA). µ n is calculated by solving the coupled Boltzmann equation in the relaxation time approximation. The coupling of wavefunctions through the barrier, screening of ionized impurities and intersubband scattering effects on µ n are investigated.