Investigation in band structures of GaAs/Al x Ga1−x As nanostructures superlattices at high magnetic field and low temperatures

Abstract

We have investigated in the band structures E(d 1), E(k z , k p ) and the effective mass m*/m 0, respectively, along the growth axis and in the plane of GaAs (d 1 = 19 nm)/Al0.3Ga0.7As (d 2 = 5 nm) superlattice, performed in the envelope function formalism. Our results show the effect of the well thickness d 1 and the temperature on the electronic structures of this superlattice. The latter has a direct band gap of 1.529 eV, and the corresponding cutoff wavelength indicates that it can be used as a near-infrared detector. The position of Fermi level, based on the magnetoresistance measurements of Smrcka et al. and Fermi–Dirac integral computation at 0.4 K, predicts that this sample exhibits n-type conductivity with a two-dimensional electron gas.