When sound meets quantum dots

THz acoustic phonons have wavelengths in the nm range and can be used as internal probes to investigate self-assemble quantum dots (QDs) structures. The interaction between delocalised acoustic phonons and an ensemble of localised electronic states yields interferences in the Raman scattering efficiency. Raman scattering interferences provide an image in reciprocal space of the electronic density and therefore allow one to probe the spatial ordering of QDs and the localisation of the electronic states. Spatial correlations functions are obtained by performing inverse Fourier transforms. Characteristic distances can be identified, provided that optical and acoustic wave reflexion effects are taken into account.