Strain distribution and optical phonons in InAs/InP self-assembled quantumdots

The strain distribution in self-assembled InAs/InP (001) quantum dots is ca lculated, using an atomistic valence force-field description. Two typical d ot shapes are considered, Strain relaxation is found to depend much on the dot shape. From these modeling results we deduce the strain-induced phonon frequency shifts. Unlike confinement, strain induces large frequency shifts . The calculations agree well with experimental results obtained by Raman s cattering, It is shown that alloying effects are small. Finally, we show th at average strain values can be obtained experimentally if one combines lon gitudinal and transverse optical-phonon Raman scattering. [S0163-1829(99)10 347-3].