Examinando por Autor "Sanz, Ruy"

Mostrando 1 - 10 de 10

Acceso Abierto
Asymmetrical magnetization processes induced by compositional gradients in ferromagnetic nanowires
(Elsevier, 2024-01-16) Fernández González, Claudia; Berja, Alba; Álvaro Gómez, Laura; Martín Rubio, C.; Mascaraque, Arantzazu; Aballe, Lucía; Sanz, Ruy; Pérez, L.; Ruiz Gómez, Sandra; Centros de Excelencia Severo Ochoa, INSTITUTO MADRILEÑO DE ESTUDIOS AVANZADOS EN NANOCIENCIA, SEV-2016-0686
Electrodeposited nanowires are an excellent scenario to study and control magnetic domain wall motion in nanostructures. In particular, the introduction of local changes in composition during the growth procedure has been proven to be very efficient for controlling the magnetization dynamics. In this work, we show the possibility of introducing compositional gradients in FeNi electrodeposited nanowires by gradually changing the Fe/Ni ratio along their axis. These compositional gradients produce an asymmetrical landscape for domain wall motion which is reflected in asymmetrical magnetization processes under an applied magnetic field. By studying nanowires with different compositional gradients we were able to correlate composition and magnetic asymmetry. Our results pave the way towards full control of the movement of domain walls along the nanowires.
Acceso Abierto
Calibration of QM-MOURA three-axis magnetometer and gradiometer
(European Geoscience Union (EGU), 2015-01-30) Díaz Michelena, M.; Sanz, Ruy; Cerdán, M. F.; Fernández, A. B.; Ministerio de Economía y Competitividad (MINECO)
MOURA instrument is a three-axis magnetometer and gradiometer designed and developed for Mars MetNet Precursor mission. The initial scientific goal of the instrument is to measure the local magnetic field in the surroundings of the lander i.e. to characterize the magnetic environment generated by the remanent magnetization of the crust and the superimposed daily variations of the field produced either by the solar wind incidence or by the thermomagnetic variations. Therefore, the qualification model (QM) will be tested in representative scenarios like magnetic surveys on terrestrial analogues of Mars and monitoring solar events, with the aim to achieve some experience prior to the arrival to Mars. In this work, we present a practical first approach for calibration of the instrument in the laboratory; a finer correction after the comparison of MOURA data with those of a reference magnetometer located in San Pablo de los Montes (SPT) INTERMAGNET Observatory; and a comparative recording of a geomagnetic storm as a demonstration of the compliance of the instrument capabilities with the scientific objectives.
Acceso Abierto
Gamma Irradiation of Magnetoresistive Sensors for Planetary Exploration
(Multidisciplinary Digital Publishing Institute (MDPI), 2012-04-02) Sanz, Ruy; Fernández, A. B.; Domínguez, J. A.; Martín Vodopivec, B.; Díaz Michelena, Marina
A limited number of Anisotropic Magnetoresistive (AMR) commercial-off-the-shelf (COTS) magnetic sensors of the HMC series by Honeywell, with and without integrated front-end electronics, were irradiated with gamma rays up to a total irradiation dose of 200 krad (Si), following the ESCC Basic Specification No. 22900. Due to the magnetic cleanliness required for these tests a special set-up was designed and successfully employed. Several parameters of the sensors were monitored during testing and the results are reported in this paper. The authors conclude that AMR sensors without front-end electronics seem to be robust against radiation doses of up to 200 krad (Si) with a dose rate of 5 krad (Si)/hour and up to a resolution of tens of nT, but sensors with an integrated front-end seem to be more vulnerable to radiation.
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.
Acceso Abierto
MOURA magnetometer for Mars MetNet Precursor Mission. Its potential for an in situ magnetic environment and surface characterization
(Universidad Complutense de Madrid, 2016-10-14) Díaz Michelena, Marina; Sanz, Ruy; Belén Fernández, A.; De Manuel, V.; Cerdán, M. F.; Apéstigue, Víctor; Domínguez, J. A.; González, Miguel; Guerrero, H.; Dolores Sabau, M.; Kilian, R.; Baeza, O.; Ríos, F.; Herraiz, M.; Vázquez, L.; Tordesillas, J. M.; Covisa, P.; Aguado, J.; Ministerio de Economía y Competitividad (MINECO)
El magnetómetro y gradiómetro MOURA forma parte de la instrumentación científica de la misión precursora de MetNet a Marte. En este trabajo se describen los objetivos de esta investigación, se recopilan las tareas de diseño y desarrollo del mismo así como su posterior calibración y se muestran las principales acciones de demostración emprendidas con el instrumento que muestran su capacidad para medidas magnéticas a bordo de aterrizadores y rovers. MOURA magnetometer and gradiometer is part of the scientific instrumentation for Mars MetNet Precursor mission. This work describes the objective of the investigation, summarizes the work done in the design and development of the sensor as well as its calibration, and shows the demonstration campaigns to show the potential of such instrument for planetary landers and rovers
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.
Restringido
Temperature Dependent Magnetization and Remanent Magnetization in Pseudo-Binary x (Fe2TiO4)-(1-x)(Fe3O4) (0.30 < x < 1.00) Titanomagnetites
(Institute of Electrical and Electronics Engineers, 2011-09-26) Sanz, Ruy; Cerdán, M. F.; Wise, A.; Díaz Michelena, M.
In this work we present preliminary results on magnetization and remanence of synthetic pseudo-binary x(Fe 2 TiO 4 )-(1-x)(Fe 3 O 4 )(0.30 <; x <; 1.00). Magnetic characterization was performed at temperature ranges from 100 K up to 400 K. The final objective is to characterize the magnetic response as a function of temperature in order to foresight the future magnetic measurements of the magnetometer included into Met-Net mission to Mars. Samples present ferromagnetic behavior with Néel temperatures above the minimum Martian temperature. An increased remanence for sample with x=0.65 has been measured possibly originated by pinning mechanism which might offer a partial explanation as to the crustal magnetism of Mars.
Acceso Abierto
Unveiling the Complex Magnetization Reversal Process in 3D Nickel Nanowire Networks
(Wiley Online Library, 2022-07-06) Ruiz Clavijo, Alejandra; Caballero Calero, Olga; Navas, David; Ordoñez Cencerrado, Amanda A.; Blanco Portals, J.; Peiró, F.; Sanz, Ruy; Martín González, Marisol; Ministerio de Economía y Competitividad (MINECO); Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Ciencia e Innovación (MICINN)
Understanding the interactions among magnetic nanostructures is one of the key factors to predict and control the advanced functionalities of 3D integrated magnetic nanostructures. In this work, the focus is on different interconnected Ni nanowires forming an intricate, but controlled, and ordered magnetic system: Ni 3D Nanowire Networks (3DNNs). These self-ordered systems present striking anisotropic magnetic responses, depending on the interconnections’ position between nanowires. To understand their collective magnetic behavior, the magnetization reversal processes are studied within different Ni 3D Nanowire Networks compared to the 1D nanowire 1DNW array counterparts. The systems are characterized at different angles using first magnetization curves, hysteresis loops, and First Order Reversal Curves techniques, which provided information about the key features that enable macroscopic tuning of the magnetic properties of the 3D nanostructures. In addition, micromagnetic simulations endorse the experiments, providing accurate modeling of their magnetic behavior. The results reveal a plethora of magnetic interactions, neither evident nor intuitive, which are the main role players controlling the collective response of the system. The results pave the way for the design and realization of 3D novel metamaterials and devices based on the nucleation and propagation of ferromagnetic domain walls both in 3D self-ordered systems and future nano-lithographed devices.