Electronic and structural properties of Mn/Cu superstructures

Abstract

We present a study of the growth of Mn/Cu/Mn/Cu slabs. The atomic short- and medium-range orders of the in situ grown multilayers have been investigated using x-ray photoelectron diffraction in the forward regime and low-energy electron diffraction techniques. Complementary results are given on the electronic structure and local magnetic moment by core level [x-ray photoelectron spectroscopy (XPS)], valence level (ultraviolet photoemission spectroscopy), and soft x-ray absorption measurements. The growth of copper overlayers on the $c(2\ifmmode\times\else\texttimes\fi{}2)\mathrm{M}\mathrm{n}/\mathrm{C}\mathrm{u}(100)$ system is found to be ordered, producing a fcc structure. We also show evidence on the growth of a second two-dimensional $c(2\ifmmode\times\else\texttimes\fi{}2)\mathrm{M}\mathrm{n}/\mathrm{C}\mathrm{u}$ alloy on top of the $p(1\ifmmode\times\else\texttimes\fi{}1)\mathrm{Cu}/c(2\ifmmode\times\else\texttimes\fi{}2)\mathrm{M}\mathrm{n}/\mathrm{C}\mathrm{u}(100)$ system, opening, therefore, the possibility of growing multilayers made of several $c(2\ifmmode\times\else\texttimes\fi{}2)\mathrm{Mn}/p(1\ifmmode\times\else\texttimes\fi{}1)\mathrm{Cu}$ units. The manganese atoms of the first and second two-dimensional magnetic alloys are found to be in a high-spin ground state in the Mn/Cu/Mn/Cu slabs and present the same XPS features, whereas the electronic structure investigated in the valence band shows slight differences.