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Ítem Solo Metadatos Influence of argon pressure on the structural properties of polycrystalline sputtered Fe0.89Ga0.11 thin films(AIP Publishing, 01-01-2021) Ramírez,G.A.; Moya-Riffo,A.; Gómez,J.E.; Malamud,F.; Rodríguez,L.M.; Fregenal,D.; Bernardi,G.; Butera,A.; Milano,J.In this work, we present a systematic study on the relation between the elastic behavior and the structural properties of polycrystalline Fe0.89Ga0.11 thin films deposited on Si(100) substrates. By carrying out pole figure (PF) measurements, we determined the evolution of the texture components, residual stress and Young's modulus (Ys) as a function of the Ar pressure. The samples display several fiber-like texture components (where the fiber axes is always along the growth direction) beside to a random component; the texture component weights depend on the Ar pressure. The study of the residual stress reveals that the samples present a tensile stress, that relaxes when the Ar pressure increases. In the case of Ys, the estimated values vary slightly within the Ar pressure range studied. Finally, the residual stress and Ys behavior is correlated with the microstructure evolution by using the orientation distribution function (ODF) simulated from the PFs.Ítem Solo Metadatos Magnetization reversal modes and coercive field dependence on perpendicular magnetic anisotropy in FePt thin films(Purpose-Led Publishing, 30-06-2023) Román, A.; Lopez Pedroso, A.; Bouzehouane, K.; Gómez, J.E.; Butera, A.; Aguirre, M.H; Medeiros Soares, M.; García, C.; Steren, L.B.The competition between shape and perpendicular magnetic anisotropies in magnetic thin films gives rise to unusual magnetic behaviors. In ferromagnetic thin films, the presence of an out-of-plane component of the magnetic anisotropy may induce a transition from planar to stripe-like magnetic domains above a critical thickness. In this article, we present a detailed study of the magnetization switching mechanism in FePt thin films, where this phenomenon is observed. Using micromagnetic simulations and experiments, we found that below the reversal mechanism is well described by the two-phase model while above this thickness the magnetization within each stripe reverses by coherent rotation. We also analyzed the out-of-plane component of the magnetic anisotropy and its temperature dependence, probing that substrate-induced strains are responsible for the abnormal coercive field behavior observed for FePt films.Ítem Solo Metadatos Coexistence of volatile and nonvolatile memristive effects in phase-separated La0.5Ca0.5MnO3-based devices(Elsevier, 06-02-2023) Ramírez, G. A.; Román Acevedo, W.; Rengifo, M.; Nuñez, J. M.; Aguirre, M. H.; Briático,J.; Rubi,D.In this work, we have investigated the coexistence of volatile and nonvolatile memristive effects in epitaxial phase-separated La0.5Ca0.5MnO3 thin films. At low temperatures (50 K), we observed volatile resistive changes arising from self-heating effects in the vicinity of a metal-to-insulator transition. At higher temperatures (140 and 200 K), we measured a combination of volatile and nonvolatile effects arising from the synergy between self-heating effects and ferromagnetic-metallic phase growth induced by an external electrical field. The results reported here add phase separated manganites to the list of materials that can electrically mimic, on the same device, the behavior of both neurons and synapses, a feature that might be useful for the development of neuromorphic computing hardware.Ítem Solo Metadatos Silica-collagen nanoformulations with extended human growth hormone release(Purpose-Led Publishing, 01-02-2023) Villarruel, Luis A.; Brie, Belén; Municoy, Sofía; Becú-Villalobos, Damasia; Desimone, Martín F.; Catalano, Paolo N.Growth hormone deficiency has been treated by the daily administration of recombinant human growth hormone (hGH) for decades. Patient compliance to this treatment is generally incomplete due to challenges including dose frequency and lack of perceived benefits. This stimulates the research on new formulations to reduce the number of periodic administrations. In this study silica nanoparticles and silica-collagen nanocomposites were evaluated for hGH loading and release. Bare nanoparticles showed higher hGH adsorption capacity than thiol- and isobutyl-bearing particles of similar diameters. Monitoring of bound protein conformation changes indicated hGH structure retention when adsorbed on bare silica nanoparticles and suggested no alterations on protein activity. Protein-loaded particles incorporated into collagen matrices (silica-collagen nanocomposites) showed a progressive protein release profile different from the observed for hGH-loaded silica nanoparticles and hGH-loaded collagen matrices. While both the collagen and the silica nanoparticle systems reached a 100 % release after 4 and 7 days respectively, silica-collagen nanocomposites showed a bi-phasic prolonged hGH release reaching approximately an 80 % after 15 days. These findings suggest that biocompatible silica-collagen nanocomposites could be used as vehicles for the prolonged delivery of hGH which could lead to a potential reduction in the number of periodic administrations.Ítem Acceso Abierto 4D Printing: The Development of Responsive Materials Using 3D-Printing Technology(MDPI, 07-12-2023) Antezana, Pablo Edmundo; Municoy, Sofia; Ostapchuk, Gabriel; Catalano, Paolo Nicolás; Hardy, John G.; Evelson, Pablo A.; Orive, Gorka; Desimone, Martin FedericoAdditive manufacturing, widely known as 3D printing, has revolutionized the production of biomaterials. While conventional 3D-printed structures are perceived as static, 4D printing introduces the ability to fabricate materials capable of self-transforming their configuration or function over time in response to external stimuli such as temperature, light, or electric field. This transformative technology has garnered significant attention in the field of biomedical engineering due to its potential to address limitations associated with traditional therapies. Here, we delve into an in-depth review of 4D-printing systems, exploring their diverse biomedical applications and meticulously evaluating their advantages and disadvantages. We emphasize the novelty of this review paper by highlighting the latest advancements and emerging trends in 4D-printing technology, particularly in the context of biomedical applications.Ítem Acceso Abierto Microcavity phonoritons – a coherent optical-to-microwave interface(Springer Nature, 18-09-2023) Kuznetsov, Alexander Sergeevich; Biermann, Klaus; Reynoso, Andres Alejandro; Fainstein, Alejandro; Santos, Paulo VenturaOptomechanical systems provide a pathway for the bidirectional optical-to-microwave interconversion in (quantum) networks. These systems can be implemented using hybrid platforms, which efficiently couple optical photons and microwaves via intermediate agents, e.g. phonons. Semiconductor exciton-polariton microcavities operating in the strong light-matter coupling regime offer enhanced coupling of near-infrared photons to GHz phonons via excitons. Furthermore, a new coherent phonon-exciton-photon quasiparticle termed phonoriton, has been theoretically predicted to emerge in microcavities, but so far has eluded observation. Here, we experimentally demonstrate phonoritons, when two exciton-polariton condensates confined in a μm-sized trap within a phonon-photon microcavity are strongly coupled to a confined phonon which is resonant with the energy separation between the condensates. We realize control of phonoritons by piezoelectrically generated phonons and resonant photons. Our findings are corroborated by quantitative models. Thus, we establish zero-dimensional phonoritons as a coherent microwave-to-optical interface.