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Ferromagnetic films down to thicknesses of tens of nanometers and composed by polycrystalline Fe and Fe2O3 nanopillars are grown in large areas by glancing angle deposition with magnetron sputtering (MS-GLAD). The morphological features of these films strongly depend on the growth conditions. Vertical or tilted nanopillars have been fabricated depending on whether the substrate is kept rotating azimuthally during deposition or not, respectively. The magnetic properties of these nanopillars films, such as hysteresis loops squareness, adjustable switching fields, magnetic anisotropy and coercivity, can be tuned with the specific morphology. In particular, the growth performed through a collimator mask mounted onto a not rotating azimuthally substrate produces almost isolated well-defined tilted nanopillars that exhibit a magnetic hardening. The first-order reversal curves diagrams and micromagnetic simulations revealed that a growth-induced uniaxial anisotropy, associated with an anisotropic surface morphology produced by the glancing angle deposition in the direction perpendicular to the atomic flux, plays an important role in the observed magnetic signatures. These results demonstrate the potential of the MS-GLAD method to fabricate nanostructured films in large area with tailored structural and magnetic properties for technological applications.

Glancing Angle Deposition (GLAD) with magnetron sputtering (MS) is an easy and versatile route to fabricate nanocolumnar films in large areas (several cm2 and above) in a single-step process, in clear contrast to other techniques in the nanoscale range such as e-beam lithography and ion-beam lithography. The morphology of the nanocolumns can be controlled depending on several parameters such as the gas pressure, the angle of inclination of the substrate and its possible rotation, the electromagnetic power, the deposition time, and the optional use of collimating masks [1-4]. Moreover, as GLAD with MS it is usually carried out at RT and does not involve chemical products (thus, without associated recycling issues), this technique is environmentally friendly. In this talk, I will start explaining the fundamentals of GLAD with MS and then I will present some recent examples of nanocolumnar films that are of interest in the field of energy and environment: Gold nanocolumnar templates for effective chemical sensing by surface-enhanced Raman scattering [5], Iron nanocolumnar films with tailored magnetic behavior [6], and Titanium oxide nanocolumnar films that exhibit photo‐induced self‐cleaning properties [7]. It will be finally shown that this latter effect can be enhanced when the nanocolumns are decorated with gold nanoparticles using a gas aggregation source that is also based on MS. References:[1] R. Alvarez et al., Nanotechnology 24, 045604 (2013). [2] R. Alvarez et al., J. Phys. D: Appl. Phys. 49, 045303 (2016). [3] A. Vitrey et al., Beilstein J. Nanotechnol. 8, 434 (2017).[4] G. Troncoso et al., Appl. Surf. Sci. 526, 146699 (2020).[5] G. Barbillon et al., Nanomaterials 12, 4157 (2022).[6] E. Navarro et al., Nanomaterials 12, 1186 (2022).[7] F. Fresno et al., Adv. Sustainable Syst. 5, 2100071 (2021).

Magnetic films of Permalloy (Ni81Fe19) with controlled defects (holes), usually called antidots arrays were synthesized by thin film deposition through sputtering and using focused ion beam (FIB) milling [1, 2]. Antidots arrays of circular holes of 80 nm were synthesized in a squared array with lattice constant of 320 nm. The Antidot shapes were controlled by increasing one direction in the circular hole, obtaining an anti-stadium shape, with short axis of 80 nm and long axis of 160 and 200 nm. This shape induces a magnetic anisotropy in the permalloy films of thicknesses of 20 and 10 nm. Magnetic characterizations were also carried out by magneto optic Kerr effect (MOKE) and magnetic force microscopy (MFM). MOKE hysteresis loops show the distribution of the magnetic anisotropy for the antidots arrays. The presence of the ordered non-magnetic holes induces a demagnetization field distribution that changes the magnetization switching mechanism. Besides, plateaus are observed in the hysteresis loops, which are related with the magnetic configuration and the density of magnetic domains in the arrays. Direct observation of the magnetic configuration was imaging at different applied field with MFM analysis in presence of a well-defined applied field using a VFM4® from Oxford instrument. Finally, Micromagnetic simulations were also carried by using Mumax3 ® to better describe the magnetic behavior

© 2022 by the authors. Licensee MDPI, This research was funded by MINECO (MAT2014-59772-C2-1-P and FIS2016-76058). We also thank the service from the MiNa Laboratory at IMN funded by Comunidad de Madrid (project S2018/NMT-4291TEC2SPACE), Comunidad de Madrid NANOMAGCOST S2018/NMT-4321, MINECO (CSIC13-4E-1794) and the EU (FEDER, FSE). In Chile we acknowledge the financial support from Redes (190158), Basal Project (AFB180001), Fondecyt 1200302, ANID-PFCHA/PostdoctoradoBecas Chile 74200122 and Dicyt-Usach 041931EM_POSTDOC. The Brazilian funding arises from São Paulo Research Foundation: 2017/10581-1 and 2020/07397-7; National Council for S., Ferromagnetic films down to thicknesses of tens of nanometers and composed by polycrystalline Fe and Fe2O3 nanopillars are grown in large areas by glancing angle deposition with magnetron sputtering (MS-GLAD). The morphological features of these films strongly depend on the growth conditions. Vertical or tilted nanopillars have been fabricated depending on whether the substrate is kept rotating azimuthally during deposition or not, respectively. The magnetic properties of these nanopillars films, such as hysteresis loops squareness, adjustable switching fields, magnetic anisotropy and coercivity, can be tuned with the specific morphology. In particular, the growth performed through a collimator mask mounted onto a not rotating azimuthally substrate produces almost isolated well-defined tilted nanopillars that exhibit a magnetic hardening. The first-order reversal curves diagrams and micromagnetic simulations revealed that a growth-induced uniaxial anisotropy, associated with an anisotropic surface morphology produced by the glancing angle deposition in the direction perpendicular to the atomic flux, plays an important role in the observed magnetic signatures. These results demonstrate the potential of the MS-GLAD method to fabricate nanostructured films in large area with tailored structural and magnetic properties for technological applications., Ministerio de Economía y Competitividad (MINECO)/FEDER, Ministerio de Economía y Competitividad (MINECO), Comunidad de Madrid, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

Glancing Angle Deposition with Magnetron Sputtering (GLAD-MS) is an easy and versatile route to fabricate arrays of nanostructures in large areas (cm2 and above) in a single processing step. In a recent work, magnetic nanopillars have been fabricated with vertical or tilted orientation depending on whether the substrate is kept rotating azimuthally during deposition or not, respectively [1]. Although the sputtering target was made of pure iron, the nanopillars were partially oxidized when they were exposed to ambient conditions, therefore the final composition was a mixture of polycrystalline -Fe and Fe2O3 and the saturation magnetization was reduced. The magnetic response was determined mainly by the interplay between the shape anisotropy of individual nanopillars and an extra growth-induced uniaxial anisotropy (associated with an anisotropic surface morphology produced by the glancing angle deposition in the direction perpendicular to the atomic flux) rather than by strong magnetic interactions. In this new work, two improvements have been introduced having in mind future applications. On the one hand, a buffer layer of Ti, 5 nm thick, has been used to enhance the adhesion. On the other hand, a capping layer of Pt, 10 nm thick, prevents the oxidation, as it has been confirmed by grazing incidence X-ray diffraction. These results pave the way for the future use of these nanopillar arrays in several applications, especially in liquid medium.

Two different nanostructures are studied in this contribution: large-area nanopillar arrays fabricated by glancing angle deposition with magnetron sputtering (MS-GLAD) and magnetic thin films perforated with long-range order arrays of nanoholes prepared by focused ion beam (patterned antidots). MS-GLAD is an easy and versatile route to fabricate arrays of nanostructures in large areas in a single processing step. In our work, nanostructured films with vertical or tilted nanopillars composed by polycrystalline Fe and Fe2O3 have been fabricated depending on whether the substrate is kept rotating azimuthally during deposition or not, respectively [1]. The magnetic properties of these films can be tuned with the specific morphology. In particular, the growth performed through a collimator mask mounted onto a not rotating azimuthally substrate produces almost isolated well-defined tilted nanopillars that exhibit a magnetic hardening. The first-order reversal curves diagrams and micromagnetic simulations revealed that a growth-induced uniaxial anisotropy, associated with an anisotropic surface morphology produced by the GLAD in the direction perpendicular to the atomic flux, plays an important role in the observed magnetic signatures. Magnetic antidots are being studied for different applications, such as magnonic crystals for microwave devices, magnetically-active plasmonic media, magnetic biosensing, and magneto-resistance sensors. In our work, a top-down approach using focused ion beam has been employed to fabricate Co/Permalloy hard-soft bilayer antidot arrays [2]. The antidots have a 40 nm diameter and two symmetries are studied: square and hexagonal. A dependence of magnetic coercivity on the relative thicknesses of the magnetically hard (Co) and soft (Permalloy) layers is found; increasing Permalloy thickness results in lower magnetic coercivity. Furthermore, the long-range periodicity of these antidots results in higher magnetic coercivity and a stronger magnetic

In the present study, we report on the successful synthesis of hollow iron oxide nanospheres. The hollow Fe3O4 nanospheres were synthesized following a four-step procedure: electrospraying spherical PVP particles, coating these particles with alumina (Al2O3) and hematite (Fe2O3) through atomic layer deposition and, finally, a thermal reduction process to degrade the polymer (PVP) and convert hematite (Fe2O3) into magnetite (Fe3O4). A structural analysis using X-ray diffraction (XRD) confirmed the effectiveness of the thermal reduction process. A morphological analysis confirmed that the four-step procedure allowed for the obtainment of hollow iron oxide nanospheres, even though the reduction process caused a contraction in the diameter of the particles of almost 300 nm, but did not affect the thickness of the walls of the hollow spheres that remained at approximately 15 nm. Magnetic properties of the hollow iron oxide nanospheres enable their use in applications where the agglomeration of magnetic nanostructures in liquid media is commonly not allowed, such as in drug encapsulation and delivery.

Co/Ni multilayers ordered according to a periodic, Fibonnacci and Thue Morse sequence have been obtained by Atomic Layer Deposition and a subsequent process of thermal reduction. The morphology of the multilayers was investigated by scanning electron microscopy, while longitudinal hysteresis curves were obtained by magneto-optical magnetometry of Kerr effect. The morphology of the films varies as a function of their sequence and thickness. Multilayers exhibit coercivities much higher than expected from samples synthesized with other methods. The control of the magnetic properties of multilayers, as a function of their sequence, may allow their use in spintronic devices.

In this work we study the oscillations of the skyrmion cores in a multilayer nanodot as a function of the number of skyrmions hosted in the system. When all the skyrmions in the nanodot have the same core radius, and after applying a perpendicular spin-polarized current, a relaxation process takes place towards an equilibrium configuration that is accompanied by coherent damped oscillations of the skyrmion cores, whose frequency depends on the number of skyrmions present in the nanodot. Additionally, we found that the oscillation frequency is directly related to the total energy of the system.

An antimicrobial polymeric bilayer structure based on the application of an acrylic coating containing hollow zinc oxide nanotubes over a polymeric substrate was developed in this work. Firstly, zinc oxide nanotubes (ZnONT) were obtained by an atomic layer deposition (ALD) process over electrospun polyvinyl alcohol nanofibers followed by polymer removal through calcination with the purpose of obtaining antimicrobial nanostructures with a high specific area. Parameters of electrospinning, ALD, and calcination processes were set in order to obtain successfully hollow zinc oxide nanotubes. Morphological studies through scanning electron microscopy (SEM) and transmission electron microscopy (TEM) microscopies confirmed the morphological structure of ZnONT with an average diameter of 180 nm and thickness of approximately 60 nm. Thermal and X-ray diffraction (XRD) analyses provided evidence that calcination completely removed the polymer, resulting in a crystalline hexagonal wurtzite structure. Subsequently, ZnONT were incorporated into a polymeric coating over a polyethylene extruded film at two concentrations: 0.5 and 1 wt. % with respect to the polymer weight. An antimicrobial analysis of developed antimicrobial materials was performed following JIS Z2801 against Staphylococcus aureus and Escherichia coli. When compared to active materials containing commercial ZnO nanoparticles, materials containing ZnONT presented higher microbial inhibition principally against Gram-negative bacteria, whose reduction was total for films containing 1 wt. % ZnONT. Antiviral studies were also performed, but these materials did not present significant viral reduction.

Magnetic films of magnetite (Fe3O4) with controlled defects, usually called antidots arrays, where synthesized by a new technique called AFIR (Artificial Force Induced Reaction), that considers the deposition of a thin film by atomic layer deposition, the generation of holes using focused ion beam milling in the case of squared and hexagonal lattices, and the subsequent thermal reduction process of antidots arrays. Magnetic characterizations were carried out by magneto optic Kerr effect, showing the enhancement of the coercivity for the antidots arrays. The presence of the ordered non-magnetic holes induces a demagnetization field distribution that change the magnetization switching mechanism, and thermal reduction from Fe2O3 to Fe3O4 produces vacancies (porosity) in the material. Magnetic behavior was studied by mean of micromagnetic simulations, in where was possible to simulate the vacancies in the continuous film and the controlled defects. This technique opens a new route of manufacture ordered antidots arrays of magnetic oxides with variable lattice parameters.

Magnetic films of magnetite (Fe3O4) with controlled defects, so-called antidot arrays, were synthesized by a new technique called AFIR. AFIR consists of the deposition of a thin film by atomic layer deposition, the generation of square and hexagonal arrays of holes using focused ion beam milling, and the subsequent thermal reduction of the antidot arrays. Magnetic characterizations were carried out by magneto-optic Kerr effect measurements, showing the enhancement of the coercivity for the antidot arrays. AFIR opens a new route to manufacture ordered antidot arrays of magnetic oxides with variable lattice parameters.

[EN] Energy bars have been introduced in the current market as a healthy alternative to enrich the athletes diet. It is essential to know the needs in each type of activity and to design them taking them into account so that they truly constitute a healthy resource to include in the diet of lovers of physical activity. In the present work, bars have been designed with easily absorbed cereals and sugars that provide enough energy to avoid hypoglycaemia and the rapid onset of fatigue. In addition, quinoa has been added, which provides proteins of high biological value due to combination of a higher proportion of essential amino acids., [ES] Las barritas energéticas se han introducido en el mercado actual como una alternativa saludable para enriquecer la dieta de los deportistas. Es indispensable conocer las necesidades en cada tipo de actividad y diseñarlas teniéndolas en cuenta para que realmente constituyan un sano recurso para incluir en la dieta de los amantes de la actividad física. En el presente trabajo se han diseñado unas barritas elaboradas con cereales y azúcares de fácil absorción que proveen de energía suficiente para evitar hipoglucemias y la rápida aparición de fatiga, pero además, se ha agregado quinoa, que proporciona proteínas de alto valor biológico debido a la combinación de una mayor proporción de aminoácidos esenciales.

We report on the study of arrays of 60 nm wide cobalt antidots, nanopatterned using focused ion beam milling. Square and hexagonal symmetry arrays have been studied, with varying antidot densities and lattice constant from 150 up to 300 nm. We find a strong increase of the arrays' magnetic coercivity with respect to the unpatterned film, which is monotonic as the antidot density increases. Additionally, there is a strong influence of the array symmetry to the in-plane magnetic anisotropy: square arrays exhibit fourfold symmetry and hexagonal arrays exhibit sixfold symmetry. The above findings are corroborated by magnetic imaging and micromagnetic modeling, which show the magnetic structure of the arrays to depend strongly on the array morphology.

Magnetic antidot arrays are groups of ordered holes patterned on a continuous magnetic film. They can be used as magnonic crystals with potential application in microwave devices [1], for magnetically-active plasmonics [2], and for biosensing applications [3]. We have followed two different routes to obtain magnetic antidots on Co, Permalloy (Py), and Co/Py films with different characteristics. Focused ion beam allowed obtaining hexagonal or square lattice antidot arrays with long-range order (hole diameter d=55nm, periodicity p=150-300nm) [4], whereas oblique deposition onto nanoporous alumina templates was used to obtain arrays with only hexagonal short-range order (d=40nm, p=105nm) [5]. The arrays were studied by magneto-optic Kerr effect, magnetic force microscopy (MFM) and micromagnetic simulations. It is shown how the coercivity increases with the density of antidots and the magnetic anisotropy axes strongly depend on the array symmetry. The MFM images show the magnetic structure of the arrays to be commensurate to their morphology, with domain walls (DW) pinned by the holes and in some cases super-DW separating linear domains (see Fig.).