Search

Correlated transparent conducting oxides (TCOs) have gained great attention, because of their unique combination of transparency and metallic character. SrVO 3 (SVO) was identified as a high-performance TCO in the visible range. Few studies have investigated band structure engineering through chemical doping to enhance the optical properties of SVO. Here, we use two different strategies by exploiting the band-filling and width of the bands derived from Vanadium to tune the screened plasma frequency ω p * and the interband transition E p - d energy, corresponding to the optical transparency window edges. For control of the band-filling strategy, it is found that Titanium doped SVO has a wide transparency window, but such a composition does not maintain the high electrical conductivity required for TCO applications. Concerning the bandwidth strategy, the doping of SrVO 3 by Calcium shows that ω p * remains located in the IR range (1.12 eV), while E p - d is blue-shifted into the UV region (3.43 eV) due to reinforced electronic correlations. By an appropriate choice of dopant, we successfully increased the size of the transparency window by around 11% from 1.94 eV (SVO) to 2.30 eV (Calcium-doped SVO), while retaining high conductivity of around 2.30 × 10 4 (S·cm -1 ) and high charge carrier density of 2.93 × 10 22 cm -3 .

SrVO 3 (SVO) is a prospective candidate to replace the conventional indium tin oxide (ITO) among the new generation of transparent conducting oxide (TCO) materials. In this study, the structural, electrical, and optical properties of SVO thin films, both epitaxial and polycrystalline, are determined during and after heat treatments in the 150-250 °C range and under ambient environment in order to explore the chemical stability of this material. The use of these relatively low temperatures speeds up the natural aging of the films and allows following the evolution of their related properties. The combination of techniques rather sensitive to the film surface and of techniques sampling the film volume will emphasize the presence of a surface oxidation evolving in time at low annealing temperatures, whereas the perovskite phase is destroyed throughout the film for treatments above 200 °C. The present study is designed to understand the thermal degradation and long-term stability issues of vanadate-based TCOs and to identify technologically viable solutions for the application of this group as new TCOs.

We have probed the structural and magnetic properties of PrVO 3 (PVO) thin films grown on the (001)-, (110)-, and (111)-oriented SrTiO 3 (STO) substrates. By changing the substrate orientation, the film out-of-plane orientation can be tuned to [110], [100]/[010], and [011]/[311], with different in-plane crystallographic variants. Accommodation of these variants on the different substrates implies different strain states, which have direct influence on the magnetic properties of PVO films. The magnetic moment of PVO films radically enhances from 0.4 μ B /f.u. for STO(001) to 2.3 μ B /f.u. for STO(111). While films on the (001)-oriented STO substrate display out-of-plane anisotropy, an in-plane anisotropy is observed for films grown on the (110)- and (111)-oriented STO substrates. In addition, a strong uniaxial magnetic anisotropy is also extracted for a partially relaxed film on the (110)-oriented STO substrate. Such findings can help oxide community for the better understanding of magnetic anisotropy in vanadate thin films, a subject that still suffer from significant lack of scientific investigations.

The integration of functional thin film materials with adaptable properties is essential for the development of new paradigms in information technology. Among them, complex oxides with perovskite structures have huge potential based on the particularly vast diversity of physical properties. Here, we demonstrate the possibility of transferring perovskite oxide materials like SrTiO 3 onto a silicon substrate using an environmentally friendly process at the nanoscale by means of a water-soluble perovskite sacrificial layer, SrVO 3 . Based on in situ monitoring atomic force microscopy and photoemission studies, we reveal that the dissolution is initiated from a strontium-rich phase at the extreme surface of SrVO 3 . The nanothick SrTiO 3 -transferred layer onto silicon presents appropriate morphology and monocrystalline quality, providing a proof of concept for the integration and development of all-perovskite-oxide electronics or "oxitronics" onto any Si-based substrate.