Design and realization of a sputter deposition system for the \textit{in situ-} and \textit{in operando-}use in polarized neutron reflectometry experiments

We report on the realization of a sputter deposition system for the in situ- and in operando-use in polarized neutron reflectometry experiments. Starting with the scientific requirements, which define the general design considerations, the external limitations and boundaries imposed by the available space at a neutron beamline and by the neutron and vacuum compatibility of the used materials, are assessed. The relevant aspects are then accounted for in the realization of our highly mobile deposition system, which was designed with a focus on a quick and simple installation and removability at the beamline. Apart from the general design, the in-vacuum components, the auxiliary equipment and the remote control via a computer, as well as relevant safety aspects are presented in detail.Comment: Submitted for publication in Nuclear Inst. and Methods in Physics Research, A. (1st revised version

Hetero-epitaxial EuO Interfaces Studied by Analytic Electron Microscopy

With nearly complete spin polarization, the ferromagnetic semiconductor europium monoxide could enable next-generation spintronic devices by providing efficient ohmic spin injection into silicon. Spin injection is greatly affected by the quality of the interface between the injector and silicon. Here, we use atomic-resolution scanning transmission electron microscopy in conjunction with electron energy loss spectroscopy to directly image and chemically characterize a series of EuO|Si and EuO|YAlO3 interfaces fabricated using different growth conditions. We identify the presence of europium silicides and regions of disorder at the EuO|Si interfaces, imperfections that could significantly reduce spin injection efficiencies via spin-flip scattering

High-quality EuO thin films the easy way via topotactic transformation

Epitaxy is widely employed to create highly oriented crystalline films. A less appreciated, butnonetheless powerful means of creating such films is via topotactic transformation, in which achemical reaction transforms a single crystal of one phase into a single crystal of a differentphase, which inherits its orientation from the original crystal. Topotactic reactions may beapplied to epitactic films to substitute, add or remove ions to yield epitactic films of differentphases. Here we exploit a topotactic reduction reaction to provide a non-ultra-high vacuum(UHV) means of growing highly oriented single crystalline thin films of the easily overoxidizedhalf-metallic semiconductor europium monoxide (EuO) with a perfection rivallingthat of the best films of the same material grown by molecular-beam epitaxy or UHV pulsedlaserdeposition. As the technique only requires high-vacuum deposition equipment, it hasthe potential to drastically improve the accessibility of high-quality single crystalline films ofEuO as well as other difficult-to-synthesize compounds