Model-independent one-dimensional imaging of interfacial structures at<1Åresolution

Abstract

The feasibility of model-independent error-correction algorithms is established for imaging buried interfacial structures in one dimension. Using the experimental structure factor modulus from x-ray specular reflectivity data, we directly compare structures derived by a modified Fienup algorithm using a known reference structure and that derived by traditional (model-dependent) least-squares fitting. This demonstrates the utility of this approach for determining one-dimensional interfacial electron density profiles with spatial resolution of $<1\phantom{\rule{0.3em}{0ex}}\mathrm{\AA{}}$. The potential applications and limitations of this approach are discussed.