The electronic contribution to the elastic constants in ultrathin films of ternary and quaternary alloys in the presence of an arbitrarily oriented magnetic field: theory and suggestion for experimental determination

摘要

An attempt is made to study the electronic contribution to the elastic constants in ultrathin films of ternary and quaternary alloys in the presence of an arbitrarily oriented magnetic field on the basis of a new electron dispersion law. It is found, takingandlattice matched to InP as examples of ternary and quaternary alloys, that the said contribution increases with increasing surface electron concentration and the band non-parabolicity enhances its magnitude. They decrease with increasing film thickness and alloy composition in various oscillatory manners. Moreover, the numerical values of the contributions in ternary materials are greater than those in quaternary compounds. An experimental method is suggested for determining the electronic contribution to the elastic constants in degenerate compounds having arbitrary dispersion laws. In addition, the well known results for wide-band-gap ultrathin materials in the absence of a magnetic field have been obtained as special cases of our generalized formulations under certain limiting conditions.