Stark-localization as a probe of nanostructure geometry

It is a central tenet of quantum mechanics that spatial resolution is limited by the wave nature of particles. Energies of stationary states reflect delocalized wave functions and cannot be ascribed to any single point. Yet, electrons confined in nanostructures become localized against the boundary by strong electric fields. Energies then reflect the local curvature of the nanostructure surface rather than entire volume. We propose using spectroscopy of Stark-localized states to map nanostructure surface curvature. By varying field direction, local curvatures are extracted from absorption spectra. Moreover, the required field strength is shown to be feasible experimentally. We use nanowires with elliptic cross section as a detailed benchmark providing quantitative error estimates and practical guide lines.