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arXiv · mtrl-th/9501004

Electronic structure of intentionally disordered AlAs/GaAs superlattices

K. A. Mader·L. -W. Wang·A. Zunger
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Abstract

We use realistic pseudopotentials and a plane-wave basis to study the electronic structure of non-periodic, three-dimensional, 2000-atom (AlAs)_n/(GaAs)_m (001) superlattices, where the individual layer thicknesses n,m = {1,2,3} are randomly selected. We find that while the band gap of the equivalent (n = m = 2) ordered superlattice is indirect, random fluctuations in layer thicknesses lead to a direct gap in the planar Brillouin zone, strong wavefunction localization along the growth direction, short radiative lifetimes, and a significant band-gap reduction, in agreement with experiments on such intentionally grown disordered superlattices.

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K. A. Mader, L. -W. Wang, A. Zunger. 1995-01-24. Electronic structure of intentionally disordered AlAs/GaAs superlattices. https://doi.org/10.1103/physrevlett.74.2555

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