Epitaxial (111) CoFe2O4 nanopillar arrays were successfully grown on flexible fluorophlogopite substrates with strong bending-related magnetic properties.
With the development of flexible electronics, the mechanical flexibility of functional materials is becoming one of the most important factors that needs to be considered in materials selection. Recently, flexible epitaxial nanoscale magnetic materials have attracted increasing attention for flexible spintronics. However, the knowledge of the bending coupled dynamic magnetic properties is poor when integrating the materials in flexible devices, which calls for further quantitative analysis. Herein, a series of epitaxial LiFe5O8 (LFO) nanostructures are produced as research models, whose dynamic magnetic properties are characterized by ferromagnetic resonance (FMR) measurements. LFO films with different crystalline orientations are discussed to determine the influence from magnetocrystalline anisotropy. Moreover, LFO nanopillar arrays are grown on flexible substrates to reveal the contribution from the nanoscale morphology. It reveals that the bending tunability of the FMR spectra highly depends on the demagnetization field energy of the sample, which is decided by the magnetism and the shape factor in the nanostructure. Following this result, LFO film with high bending tunability of microwave magnetic properties, and LFO nanopillar arrays with stable properties under bending are obtained. This work shows guiding significances for the design of future flexible tunable/stable microwave magnetic devices.
Heusler compound Mn2CoAl (MCA) is attracting more attentions due to many novel properties, such as high resistance, semiconducting behavior and suggestion as a spin-gapless material with a low magnetic moment. In this work, Mn2CoAl epitaxial thin film was prepared on MgO(100) substrate by magnetron sputtering. The transport property of the film exhibits a semiconducting-like behavior. Moreover, our research reveals that perpendicular magnetic anisotropy (PMA) can be induced in very thin Mn2CoAl films resulting from Mn-O and Co-O bonding at Mn2CoAl/MgO interface, which coincides with a recent theoretical prediction. PMA and low saturation magnetic moment could lead to large spin-transfer torque with low current density in principle, and thus our work may bring some unanticipated Heusler compounds into spintronics topics such as the domain wall motion and the current-induced magnetization reversal.
Recent development in magnetic nanostructures has promoted flexible electronics into the application of integrated devices. However, the magnetic properties of flexible devices strongly depend on the bending states. In order to realize the design of new flexible devices driven by an external field, the first step is to make the magnetic properties insensitive to the bending. Herein, a series of LiFe 5 O 8 nanopillar arrays were fabricated, whose microwave magnetic properties can be modulated by tuning the nanostructure. This work demonstrates that nanostructure engineering is useful to control the bending sensitivity of microwave magnetism and further design stable flexible devices.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.