Two-dimensional GaAs/AlGaAs superlattice structures for solar cell applications: ultimate efficiency estimation

TL;DR

This paper models a 2D GaAs/AlGaAs superlattice to estimate its maximum potential efficiency for solar energy conversion, showing it can outperform individual materials across various structural parameters.

Contribution

It provides the first detailed calculation of the band structure and efficiency limits of 2D GaAs/AlGaAs superlattices for solar cells, exploring how structural parameters influence performance.

Findings

Superlattice efficiency exceeds that of individual materials.

Efficiency depends on filling fraction, lattice constant, and Al concentration.

Optimal parameters significantly enhance solar energy conversion potential.

Abstract

We calculate the band structure of a two-dimensional GaAs/AlGaAs superlattice and estimate the ultimate efficiency of solar cells using this type of structure for solar energy conversion. The superlattice under consideration consists of gallium arsenide rods forming a square lattice and embedded in aluminium gallium arsenide. The ultimate efficiency is determined versus structural parameters including the filling fraction, the superlattice constant, the rod geometry and the concentration of Al in the matrix material. The calculated efficiency of the superlattice proves to exceed the efficiency of each component material in the monolithic state in a wide range of parameter values.