Examinando por Autor "Sanz, Ruy"

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Restringido
Magnetic interactions in ordered cobalt three-dimensional nanonetworks
(EMS, 2023-08-27) Ruiz Clavijo, Alejandra; Caballero Calero, Olga; Navas, David; Vivas, Laura G.; Martín Rubio, C.; Sanz, Ruy; Martín González, Marisol; Agencia Estatal de Investigación (AEI)
"Three-Dimensional (3D) magnetic nanostructures allow the generation and control of new effects able to give rise to the next generation of functional magnetic nanostructured metamaterials and devices[1]. This work reports the results on the synthesis and characterization of different interconnected Co nanowires forming a dense and ordered magnetic system: Co 3D Nanowire Networks (3DNN). These nanostructures were synthesized by the electrodeposition of Co in 3D ordered porous alumina templates [2] [3] [4]. The route allows to control the order and some geometric features compared to other synthesis approaches [1]. The resulting 3DNN consists of hexagonal ordered nanowires with an inter-wire distance of 65 nm and 50 nm in diameter. These nanowires are interconnected with a net of perpendicular or transversal nanowires (TNW) of ≈ 30 nm in diameter. Meanwhile the TNW are distributed in levels with a well defined distance between them of 550 nm. The magnetic characterization consisted in hysteresis loops, first magnetization curves and first order reversal curves (FORC) at 0º (in-plane, IP) 30º, 60º and 90º (out of plane, OOP) from perpendicular NW main axis. 1.D. Bhattacharya, et al. Nano Lett. (2022), 22, 24, 10010–10017. 2.J. Martín, et. al., Nat. Commun. 5, (2014) 5130. 3.A. Ruiz-Clavijo, et al. Phys. Status Solidi RRL, 13 (2019), 1900263. 4.A. Ruiz-Clavijo, et al., Adv. Electron. Mater. 8, (2022) 2200342"
Restringido
Magnetic study of Cobalt three dimensional nanonetworks: First Order Reversal Curves, hysteresis loops and first magnetization curves
(Institute of Electrical and Electronics Engineers, 2023-05-19) Ruiz Clavijo, Alejandra; Caballero Calero, Olga; Navas, David; Martín Rubio, C.; Sanz, Ruy; Martín González, Marisol
Three-Dimensional (3D) magnetic nanostructures will be the next generation of functional magnetic nanostructured metamaterials. In this work, we report some of our recent results on the synthesis and characterization of different interconnected Co nanowires forming a dense and ordered magnetic system: Co 3D Nanowire Networks (3DNN). The 3DNN presents anisotropic magnetic responses. We used first magnetization curves, hysteresis loops, and first order reversal curves techniques to characterize the systems, which provide information about the key magnetic properties of the 3D nanostructure.
Acceso Abierto
Mars MOURA magnetometer demonstration for high-resolution mapping on terrestrial analogues
(European Geoscience Union (EGU), 2016-05-19) Díaz Michelena, M.; Kilian, R.; Sanz, Ruy; Ríos, F.; Baeza, O.; Ministerio de Economía y Competitividad (MINECO)
Satellite-based magnetic measurements of Mars indicate complex and very strong magnetic anomalies, which led to an intensive and long-lasting discussion about their possible origin. To make some progress in the investigation of the origin of these anomalies the MOURA vector magnetometer was developed for in situ measurements on Mars. In this work we propose the utilisation of such an instrument for future planetary on-ground surveys. The proof of its suitability is seen through testing it on various terrestrial analogues characterised by the distinct magnetic anomalies of their basement rocks: (1) a magnetite body of EL Laco (up to +110 000 nT) and its transition to surrounding andesites ( <  +2000 nT) in the northern Andes of Chile showing the highest local magnetic anomalies. The magnetite-bearing ore body has highly variable local anomalies due to its complex formation history where a significant dispersion in palaeo-orientations has been previously reported, while our vector data show relatively uniform and probably induced declinations. (2) A basaltic spatter cone of the Pali Aike volcanic field, in southern Chile, was characterised by very strong magnetic anomalies along the crater rim (up to +12 000 nT), controlled by the amount of single domain magnetites in the ground mass of the basalts. Due to their strong remanent signature, palaeo-declinations of the lavas and reorientations of collapsed blocks could be constrained by the vector data. (3) The Monturaqui meteorite crater (350 m diameter), in northern Chile, shows significant variations of its anomalies (from −2000 to >  +6000 nT) in restricted areas of several square metres along its crater rim related to unexposed iron-bearing fragments of the impactor while its granitic and ignimbritic target rocks exhibit only very weak anomalies. (4) An area with several amphibolitic dykes, which cross-cut a Cretaceous granitoid in the southernmost Andes, where a decimetre-scale mapping was performed. In this case, pyrrhotite is the only magnetic carrier. It was formed during hydrothermal processes within the dykes. Very low (+40 to +120 nT) positive magnetic anomalies clearly depict the amount of 1–4 vol % pyrrhotite in these dykes, which is important as a mineralogical indicator as well as to detect associated gold and copper enrichment.
Restringido
Nanostructured metamaterials for the thermal and electromagnetic isolation of cryostats
(SPIE, 2024-08-26) Vivas, Laura G.; Ramos Somolinos, D.; Martín Rubio, C.; Rivelles García, Alejandro; Madueño Custodio, Laura; Ruiz Clavijo, Alejandra; Díaz, Alberto; Schneider, Marc; Plaza Gallardo, Borja; Poyatos Martínez, David; Del Hoyo, J. C.; Caballero Calero, Olga; Worgull, M.; Martín Iglesias, Santiago; Martín Vodopivec, B.; Maicas, M.; Navas, David; Martín González, Marisol; Sanz, Ruy
In terms of thermal and electromagnetic isolation properties, Nanostructured Metamaterials may present important advantages compared to current employed materials. In this work, we present the synthesis routes and the preliminary characterization results of some metamaterials based on Poly-ether-ether-ketone and nanostructured anodic oxides, with low thermal conductivity, combined with Au nanocolumns and three-dimensional nanonetworks. The results reveals proper magnetic and electromagnetic properties and suggest their suitable use under vacuum and cryogenic conditions.