First-principles calculation of the elastic constants of AlAs

Abstract

We use an ab initio pseudopotential method within the local-density approximation to determine the full set of elastic moduli of AlAs which have not been directly established experimentally. We find $C_{11}$=1.16, $C_{12}$=0.55, and $C_{44}$=0.57 Mbar, close to those known for GaAs. Since similar calculations for GaAs and other materials produce results in close agreement with experiment, we conclude that our results for AlAs are also reliable.