Self-assembled growth of Sr(Ti,Fe)O3–CoFe2O4 magnetic nanocomposite thin films

Abstract

Iron-substituted SrTiO3-CoFe2O4 nanocomposite thin films were grown by pulsed laser deposition on (001) SrTiO3 substrates, and their structure and magnetic properties were compared with those of single phase films. Both CoFe2O4 thin films grown in oxygen and under vacuum exhibited an in-plane magnetic easy axis, but films grown in vacuum exhibited polycrystallinity and additional metallic phases. Sr(Ti,Fe)O3 grown under high vacuum conditions showed an out-of-plane easy axis, whereas films grown in oxygen had no ferromagnetism. Nanocomposite thin films grown under high vacuum exhibited a terraced microstructure with out-of-plane easy axis. On the other hand, nanocomposites grown in oxygen exhibited two-step switching and much higher saturation magnetization. The results are consistent with dominant magnetoelastic anisotropy.

Self-Assembled Multiphase Nanocomposite SrCo1–xFexO3-δ Thin Films with Voltage-Controlled Magnetism for Spintronic Applications

“…10–100 nm, embedded in a matrix of a second phase. Nanocomposites exhibit the properties of both phases and often reveal interfacially mediated cross-coupling between those properties, for example, magnetoelectric coupling in a nanocomposite consisting of a ferroelectric phase and a magnetic phase. − Nanocomposites have been synthesized from many combinations of materials, most commonly perovskite (e.g., BiFeO 3 , BaTiO 3 , PbTiO 3 , SrTiO 3 , La 0.8 Sr 0.2 CoO 3 ) and spinel (e.g., CoFe 2 O 4 , MgFe 2 O 4 , NiFe 2 O 4 , Mn 0.5 Zn 0.5 Fe 2 O 4 ), ,− but have also included ZnO, Sm 2 O 3 , Cu oxides, and metal nanowires or nanoparticles. , In our prior work, pulsed laser codeposition from SCO and Fe 3 O 4 targets was used to form a nanocomposite consisting of an SCFO matrix and Co spinel (Co 3 O 4 ) pillars of diameter ∼50 nm, where the coherent interfaces enable strain transfer between the two phases …”

Phase Formation and Exchange Bias in LuFeO3–CoxFe3–xO4 Nanocomposite Films

“…As the contrast in the HAADF STEM images is approximately proportional to the atomic number, Z 1.7 , LFO appears brighter than CFO because of the heavy rare earth element Lu ( Z = 71) compared to Co ( Z = 27). The vertical microstructures revealed in cross-section are typical of vertically aligned nanostructures with a range of thicknesses. ,, …”

“…The vertical microstructures revealed in cross-section are typical of vertically aligned nanostructures with a range of thicknesses. 15,31,32 Figure 2c shows the presence of spinel CFO and perovskite LFO in C1F2(90)−LF14(90) which meet in (111)/(111) p interfaces oriented at 55°to the substrate. 15 In contrast, C3(90)−LF06(90) (Figure 2d) shows three crystal structures: perovskite, spinel, and rocksalt.…”

Progress and perspective on polymer templating of multifunctional oxide nanostructures

“…Different sets of parameters like substrate orientation, phase composition, and growth rate lead to rich morphologies such as embedded rods, embedded triangles, labyrinth-like morphology, lamellar-like morphology, etc. 97,101,102,107,109,111,112 The size and position of CoFe 2 O 4 (CFO) nanopillars formed in the self-assembly process are not defined. To improve the regularity, various patterning techniques have been utilized.…”