First-principles calculations of strontium on Si(001)

This paper reports state-of-the-art electronic structure calculations on the deposition of strontium on the technologically relevant, (001) orientated silicon surface. We identified the surface reconstructions from $0--\frac{4}{3}$ monolayers and relate them to experimentally reported data. A phase diagram is proposed. We predict phases at $\frac{1}{6},$ $\frac{1}{4},$ $\frac{1}{2},$ $\frac{2}{3},$ and 1 monolayers. Our results are expected to provide valuable information in order to understand heteroepitaxial growth of a prominent class of high-$K$ oxides around ${\mathrm{SrTiO}}_{3}.$ The insight obtained for strontium is expected to be transferable to other alkaline-earth metals.