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Bi₂FeCrO₆ thin films were epitaxially grown by pulsed laser deposition on (100)-oriented LaAlO₃, (LaAlO₃)_0.3(Sr₂LaTaO₆)_0.7 and SrTiO₃ single crystalline substrates with and without epitaxial CaRuO₃ buffered layer. The in-plane compressive strain induces monoclinic distortion of the Bi₂FeCrO₆ lattice cell. The strain originates from lattice mismatch between CaRuO₃ and single crystal substrates. The similar crystal structure of the substrate and the layer lead to coherent epitaxial growth of the heterostructures and avoid strain relaxation in particular for BFCO films deposited on LaAlO₃ substrates. The ferroelectric character is demonstrated for all grown BFCO films. The residual in-plane strain weakly affects the effective piezoelectric coefficient of BFCO layers.

Oxide precursors NdCaCo${}_{1-x}$Ni_xO_n ($x=0;0.2;0.4;0.6;0.8;1$) are obtained by the solid-state synthesis method at 1100${}^{\circ }$C. According to XRD analysis, the main components of these precursors are complex oxides with K₂NiF₄-like structure at $x\le 0.8$ and with rhombically distorted K₂NiF₄ structure at $x=1$. A thermal decomposition of these precursors in the mixture of CH₄/O${}_2=2$ at T $\ge$ 800${}^{\circ }$C results in the formation of dense metal-oxide nanocomposite particles. As-obtained nanocomposites demonstrated a considerable catalytic activity and selectivity in the reaction of partial oxidation of methane; their catalytic properties vary non-monotonously with Co/Ni ratio. The maximum CH₄ conversion and CO selectivity at 820${}^{\circ }$C is demonstrated by the composite comprising Nd₂O₃, CaO, NiO and Ni metal nanoparticles.

We demonstrate an electric field control of spin lifetime at room temperature, across a semiconducting interface of Nb:STO using Ni/AlO_x as spin injection contacts. We achieve this by a careful tailoring of the potential landscape in Nb:STO, driven by the strong response of the intrinsically large dielectric permittivity in STO to electric fields. The built-in electric field at the Schottky interface with Nb:STO tunes the intrinsic Rashba spin–orbit fields leading to a bias dependence of the spin lifetime in Nb:STO. Such an electric field driven modulation of spin accumulation has not been reported earlier using conventional semiconductors. This not only underpins the necessity of a careful design of the spin injection contacts but also establishes the importance of Nb:STO as a rich platform for exploring spin–orbit driven phenomena in complex oxide based spintronic devices.