199 results on '"Muñoz-Noval, A."'
Search Results
2. Exchange bias coupling and bipolar resistive switching at room temperature on GaSb/Mn multilayers for resistive memories applications
- Author
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Calderón, Jorge A., Quiroz, Heiddy P., Terán, Cristian L., Manso-Silván, M., Dussan, A., and Muñoz Noval, Álvaro
- Published
- 2023
- Full Text
- View/download PDF
3. Realization of macroscopic ratchet effect based on nonperiodic and uneven potentials
- Author
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Rollano, V., Gomez, A., Muñoz-Noval, A., Velez, M., de Ory, M. C., Menghini, M., Gonzalez, E. M., and Vicent, J L
- Subjects
Condensed Matter - Superconductivity - Abstract
Ratchet devices allow turning an ac input signal into a dc output signal. A ratchet device is set by moving particles driven by zero averages forces on asymmetric potentials. Hybrid nanostructures combining artificially fabricated spin-ice nanomagnet arrays with superconducting films have been identified as a good choice to develop ratchet nanodevices. In our case, the asymmetric potentials are provided by charged N\'eel walls located in the vertices of the magnetic honeycomb array, whereas the role of moving particles is played by superconducting vortices. We have experimentally obtained ratchet effect for different spin ice I configurations and for vortex lattice moving parallel or perpendicular to the magnetic easy axes. Remarkably, the ratchet magnitudes are similar in all the experimental runs; i. e. different spin ice I configurations and in both relevant directions of the vortex lattice motion. We have simulated the interplay between vortex motion directions and a single asymmetric potential. It turns out vortices interact with uneven asymmetric potentials, when they move with trajectories crossing charged N\'eel walls with different orientations. Moreover, the appropriate asymmetric pair potentials which generate the local ratchet effect have been identified. In this rocking ratchet the particles (vortices) on the move are interacting each other (vortex lattice); therefore, the ratchet local effect turns into a global macroscopic effect. In summary, this ratchet device benefits from interacting particles moving in robust and topological protected type I spin ice landscapes., Comment: 21 pages, 13 figures
- Published
- 2021
- Full Text
- View/download PDF
4. Little-Parks Effect Governed by Magnetic Nanostructures with Out-of-Plane Magnetization Little-Parks Effect Governed by Magnetic Nanostructures with Out-of-Plane Magnetization
- Author
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de Ory, M. C., Rollano, V., Gomez, A., Menghini, M., Muñoz-Noval, A., Gonzalez, E. M., and Vicent, J. L.
- Subjects
Condensed Matter - Superconductivity - Abstract
Little-Parks effect names the oscillations in the superconducting critical temperature as a function of the magnetic field. This effect is related to the geometry of the sample. In this work, we show that this effect can be enhanced and manipulated by the inclusion of magnetic nanostructures with perpendicular magnetization. These magnetic nanodots generate stray fields with enough strength to produce superconducting vortex-antivortex pairs. So that, the L-P effect deviation from the usual geometrical constrictions is due to the interplay between local magnetic stray fields and superconducting vortices. Moreover, we compare our results with a low-stray field sample (i.e. with the dots in magnetic vortex state) showing how the enhancement of the L-P effect can be explained by an increment of the effective size of the nanodots., Comment: 14 pages, 6 figures
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- 2020
- Full Text
- View/download PDF
5. Vortex dynamics controlled by local superconducting enhancement
- Author
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Rollano, V., Gomez, A., Muñoz-Noval, A., del Valle, J., Menghini, M., de Ory, M. C., Prieto, J. L., Navarro, E., Gonzalez, E. M., and Vicent, J. L.
- Subjects
Condensed Matter - Superconductivity - Abstract
A controlled local enhancement of superconductivity yields unexpected modifications in the vortex dynamics. This local enhancement has been achieved by designing an array of superconducting Nb nanostructures embedded in a V superconducting film. The most remarkable findings are: i) vanishing of the main commensurability effect between the vortex lattice and the array unit cell, ii) hysteretic behavior in the vortex dynamics, iii) broadening of the vortex liquid phase and iv) strong softening of the vortex lattice. These effects can be controlled and they can be quenched by reducing the Nb array superconducting performance applying an in-plane magnetic field. These results can be explained by taking into account the repulsive potential landscape created by the superconducting Nb nanostructures on which vortices move., Comment: 16 pages, 8 figures
- Published
- 2019
- Full Text
- View/download PDF
6. Exchange bias coupling and bipolar resistive switching at room temperature on GaSb/Mn multilayers for resistive memories applications
- Author
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Jorge A. Calderón, Heiddy P. Quiroz, Cristian L. Terán, M. Manso-Silván, A. Dussan, and Álvaro Muñoz Noval
- Subjects
Medicine ,Science - Abstract
Abstract This work present structural, morphological, magnetic, and electrical properties of GaSb/Mn multilayer deposited via DC magnetron sputtering at room temperature and at 423 K. The samples are characterized by forming layers of 3, 6 and 12 periods of the GaSb/Mn structure. Through XRD patterns, it was possible to stablish the formation of GaSb, Mn3Ga, and Mn2Sb2 phases. FTIR measurements present an optical interference associated with periodicity and the homogenous thickness of the layers. HR-SEM shows the multilayer architecture with columnar microstructure in the formation of layers with grain nucleation on the surface. A ferromagnetic-like behavior was observed in the multilayers at room temperature related to the domains and interlayers interaction. Additionally, the hysteresis curves present shifts attributed to the effect of exchange bias coupling. I-V curves show RESET-SET states of the multilayer system with bipolar resistive behavior, which can be modified by external magnetic fields. The resistive switching evidenced corresponds to the conductive mechanism based on the capacitive conductance and the formation of conductive filaments in multilayer structure.
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- 2023
- Full Text
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7. Topologically protected superconducting ratchet effect generated by spin-ice nanomagnets
- Author
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Rollano, V., Muñoz-Noval, A., Gomez, A., Bango, F. Valdes, Martin, J. I., Velez, M., Osorio, M. R., Granados, D., Gonzalez, E. M., and Vicent, J. L.
- Subjects
Condensed Matter - Superconductivity - Abstract
We have designed, fabricated and tested a robust superconducting ratchet device based on topologically frustrated spin-ice nanomagnets. The device is made of a magnetic Co honeycomb array embedded in a superconducting Nb film. This device is based on three simple mechanisms: i) the topology of the Co honeycomb array frustrates in-plane magnetic configurations in the array yielding a distribution of magnetic charges which can be ordered or disordered with in-plane magnetic fields, following spin-ice rules, ii) the local vertex magnetization, which consists of a magnetic half vortex with two charged magnetic N\'eel walls, iii) the interaction between superconducting vortices and the asymmetric potentials provided by the N\'eel walls. The combination of these elements leads to a superconducting ratchet effect. Thus, superconducting vortices driven by alternating forces and moving on magnetic half vortices generate a unidirectional net vortex flow. This ratchet effect is independent of the distribution of magnetic charges in the array., Comment: 17 pages, 7 figures
- Published
- 2018
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8. A combined micro-Raman, X-ray absorption and magnetic study to follow the glycerol-assisted growth of epsilon-iron oxide sol-gel coatings
- Author
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López-Sánchez, Jesús, Serrano, Aída, del Campo, Adolfo, Muñoz-Noval, Álvaro, Salas-Colera, Eduardo, Cabero, Mariona, Varela, María, Abuín, Manuel, Castro, Germán R., Rubio-Zuazo, Juan, Rodríguez de la Fuente, Óscar, and Carmona, Noemí
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- 2022
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9. Tuning the Metal-Insulator Transition Temperature by the Controlled Generation of Oxygen Vacancies on La0.7Ca0.3MnO3-x Epitaxial Thin Films
- Author
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Colera, E. Salas, primary, Muñoz-Noval, A., additional, Sebastiani-Tofano, E., additional, Castro, G.R., additional, and Rubio-Zuazo, J., additional
- Published
- 2024
- Full Text
- View/download PDF
10. Realization of macroscopic ratchet effect based on nonperiodic and uneven potentials
- Author
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V. Rollano, A. Gomez, A. Muñoz-Noval, M. Velez, M. C. de Ory, M. Menghini, E. M. Gonzalez, and J. L. Vicent
- Subjects
Medicine ,Science - Abstract
Abstract Ratchet devices allow turning an ac input signal into a dc output signal. A ratchet device is set by moving particles driven by zero averages forces on asymmetric potentials. Hybrid nanostructures combining artificially fabricated spin ice nanomagnet arrays with superconducting films have been identified as a good choice to develop ratchet nanodevices. In the current device, the asymmetric potentials are provided by charged Néel walls located in the vertices of spin ice magnetic honeycomb array, whereas the role of moving particles is played by superconducting vortices. We have experimentally obtained ratchet effect for different spin ice I configurations and for vortex lattice moving parallel or perpendicular to magnetic easy axes. Remarkably, the ratchet magnitudes are similar in all the experimental runs; i. e. different spin ice I configurations and in both relevant directions of the vortex lattice motion. We have simulated the interplay between vortex motion directions and a single asymmetric potential. It turns out vortices interact with uneven asymmetric potentials, since they move with trajectories crossing charged Néel walls with different orientations. Moreover, we have found out the asymmetric pair potentials which generate the local ratchet effect. In this rocking ratchet the particles (vortices) on the move are interacting each other (vortex lattice); therefore, the ratchet local effect turns into a global macroscopic effect. In summary, this ratchet device benefits from interacting particles moving in robust and topological protected type I spin ice landscapes.
- Published
- 2021
- Full Text
- View/download PDF
11. Local disorder and structure relation induced by magnetic exchange interactions in A2(Mo1−yMny)2O7 pyrochlores
- Author
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Castellano, C., Scavini, M., Berti, G., Rubio-Marcos, F., Lamura, G., Sanna, S., Salas-Colera, E., Muñoz-Noval, Á., Cimberle, M.R., and Demartin, F.
- Published
- 2021
- Full Text
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12. The role of surface to bulk ratio on the development of magnetic anisotropy in high Ga content Fe100-xGax thin films
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Muñoz-Noval, A., Fin, S., Salas-Colera, E., Bisero, D., and Ranchal, R.
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- 2018
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13. Correlation between local structure and magnetic behavior in co-sputtered TbxFe73Ga27−x (7 ≤ x ≤ 11) thin films
- Author
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Muñoz-Noval, A., Salas-Colera, E., Bartolomé, P., Serrano, A., Castro, G.R., and Ranchal, R.
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- 2017
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14. Anomalous local lattice disorder and distortion in A2Mo2O7 pyrochlores
- Author
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Castellano, C., Berti, G., Rubio-Marcos, F., Lamura, G., Sanna, S., Salas-Colera, E., Brambilla, A., Muñoz-Noval, Á., Duò, L., and Demartin, F.
- Published
- 2017
- Full Text
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15. Morphological, structural and magnetic evolution of sputtered Fe70Ga30 thin films upon annealing in oxygen atmosphere
- Author
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Álvarez-Álvarez, P., Prados, A., Muñoz-Noval, A., and Ranchal, R.
- Published
- 2017
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16. X-Ray Nanothermometry of Nanoparticles in Tumor-Mimicking Tissues under Photothermia
- Author
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López-Méndez R., Reguera J., Fromain A., Serea E.S.A., Céspedes E., Teran F.J., Zheng F., Parente A., García M.Á., Fonda E., Camarero, Julio0, Wilhelm C., Muñoz-Noval Á., Espinosa, Ana, López-Méndez R., Reguera J., Fromain A., Serea E.S.A., Céspedes E., Teran F.J., Zheng F., Parente A., García M.Á., Fonda E., Camarero, Julio0, Wilhelm C., Muñoz-Noval Á., and Espinosa, Ana
- Published
- 2023
17. Influence of the sputtering flow regime on the structural properties and magnetic behavior of Fe-Ga thin films (Ga ∼ 30 at.%)
- Author
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Muñoz Noval, Álvaro, Ordóñez Fontes, A., Ranchal Sánchez, Rocío, Muñoz Noval, Álvaro, Ordóñez Fontes, A., and Ranchal Sánchez, Rocío
- Abstract
©2016 American Physical Society. This paper has been financially supported through of the Spanish Ministry of Economy and Competitiveness (MINECO), MAT2015-66888-C3-3-R. We thank “CAI Difracción de rayos-X” of Universidad Complutense de Madrid for the x-ray diffractometry measurements and Instituto de Sistemas Optoelectrónicos y Microtecnología (ISOM) for the use of some of its facilities. We also thank BM25-SpLine, the Spanish CRG at ESRF for providing beam time., In this paper we analyze the structure of Fe-Ga layers with a Ga content of ∼30 at.% deposited by the sputtering technique under two different regimes. We also studied the correlation between the structure and magnetic behavior of the samples. Keeping the Ar pressure fixed, we modified the flow regime from ballistic to diffusive by increasing the distance between the target and the substrate. X-ray diffraction measurements have shown a lower structural quality when growing in the diffusive flow. We investigated the impact of the growth regime by means of x-ray absorption fine structure (XAFS) measurements and obtained signs of its influence on the local atomic order. Full multiple scattering and finite difference calculations based on XAFS measurements point to a more relevant presence of a disordered A2 phase and of orthorhombic Ga clusters on the Fe-Ga alloy deposited under a diffusive regime; however, in the ballistic sample, a higher presence of D0_3/B2 phases is evidenced. Structural characteristics, from local to long range, seem to determine the magnetic behavior of the layers. Whereas a clear in-plane magnetic anisotropy is observed in the film deposited under ballistic flow, the diffusive sample is magnetically isotropic. Therefore, our experimental results provide evidence of a correlation between flow regime and structural properties and its impact on the magnetic behavior of a rather unexplored compositional region of Fe-Ga compounds., Ministerio de Economía y Competitividad (MINECO), Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub
- Published
- 2023
18. X-Ray Nanothermometry of Nanoparticles in Tumor-Mimicking Tissues under Photothermia
- Author
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Comunidad de Madrid, Ministerio de Ciencia e Innovación (España), Consejo Superior de Investigaciones Científicas (España), López-Méndez, Rosalía, Reguera, Javier, Fromain, Alexandre, Serea, Esraa Samy Abu, Céspedes, Eva, Teran, Francisco José, Zheng, Fangyuan, Parente, Ana, García García-Tuñón, Miguel Ángel, Fonda, Emiliano, Camarero, Julio, Wilhelm, Claire, Muñoz-Noval, Álvaro, Espinosa, Ana, Comunidad de Madrid, Ministerio de Ciencia e Innovación (España), Consejo Superior de Investigaciones Científicas (España), López-Méndez, Rosalía, Reguera, Javier, Fromain, Alexandre, Serea, Esraa Samy Abu, Céspedes, Eva, Teran, Francisco José, Zheng, Fangyuan, Parente, Ana, García García-Tuñón, Miguel Ángel, Fonda, Emiliano, Camarero, Julio, Wilhelm, Claire, Muñoz-Noval, Álvaro, and Espinosa, Ana
- Abstract
[EN] Temperature plays a critical role in regulating body mechanisms and indicating inflammatory processes. Local temperature increments above 42 °C are shown to kill cancer cells in tumorous tissue, leading to the development of nanoparticle-mediated thermo-therapeutic strategies for fighting oncological diseases. Remarkably, these therapeutic effects can occur without macroscopic temperature rise, suggesting localized nanoparticle heating, and minimizing side effects on healthy tissues. Nanothermometry has received considerable attention as a means of developing nanothermosensing approaches to monitor the temperature at the core of nanoparticle atoms inside cells. In this study, a label-free, direct, and universal nanoscale thermometry is proposed to monitor the thermal processes of nanoparticles under photoexcitation in the tumor environment. Gold-iron oxide nanohybrids are utilized as multifunctional photothermal agents internalized in a 3D tumor model of glioblastoma that mimics the in vivo scenario. The local temperature under near-infrared photo-excitation is monitored by X-ray absorption spectroscopy (XAS) at the Au L-edge (11 919 eV) to obtain their temperature in cells, deepening the knowledge of nanothermal tumor treatments. This nanothermometric approach demonstrates its potential in detecting high nanothermal changes in tumor-mimicking tissues. It offers a notable advantage by enabling thermal sensing of any element, effectively transforming any material into a nanothermometer within biological environments.
- Published
- 2023
19. GaSb/Mn multilayers structures fabricated by DC magnetron sputtering: Interface feature and nano-scale surface topography
- Author
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Calderón, Jorge A., Quiroz, Heiddy P., Manso Silván, Miguel, Muñoz Noval, Álvaro, Dussan, A., Méndez, H., and UAM. Departamento de Física de Materiales
- Subjects
Electronic applications ,Spintronic devices ,Multilayer structure ,Física ,GaSb/Mn multilayers ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Abstract
The multilayer structure is a well-studied architecture for electronic and optoelectronic applications and more recently in spintronic devices. In this work, we present the structural, morphological, topographical, and magnetic properties of GaSb/Mn multilayers deposited via DC magnetron sputtering at room temperature and 423 K. Raman measurements evidence the formation of p-type GaSb layers with a contribution of electrons in the multilayer due to the neighboring Mn layer and the formation of effective interlayers. HR-SEM measurements show the multilayer architecture with columnar microstructure in the layer’s formation, while AFM micrographs allowed observing the changes in grain sizes (between 129 and 187 nm) and roughness (between 1.47 nm and 6.28 nm) with increasing number of layers. The formation of the interlayers between the GaSb and Mn layer was assayed in-depth spectroscopically via Rutherford backscattering studies. These interlayers were associated with diffusion processes during deposition and contributed to the magnetic behavior of multilayers. A ferromagnetic-like behavior was observed in the multilayers
- Published
- 2022
20. Realization of macroscopic ratchet effect based on nonperiodic and uneven potentials
- Author
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J. L. Vicent, Elvira M. Gonzalez, M. C. de Ory, M. Menghini, V. Rollano, María Vélez, Alicia Gomez, Álvaro Muñoz-Noval, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), European Commission, Ministerio de Economía y Competitividad (España), Comunidad de Madrid, Centros de Excelencia Severo Ochoa, INSTITUTO MADRILEÑO DE ESTUDIOS AVANZADOS EN NANOCIENCIA, SEV-2016-0686, and Agencia Estatal de Investigación (AEI)
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Physics ,Superconductivity ,Multidisciplinary ,Condensed matter physics ,Física de materiales ,Condensed Matter - Superconductivity ,Science ,Ratchet ,FOS: Physical sciences ,Ratchet effect ,Nanomagnet ,Article ,Vortex ,Superconductivity (cond-mat.supr-con) ,Spin ice ,Lattice (module) ,Nanoscience and technology ,Física del estado sólido ,Perpendicular ,Medicine - Abstract
Ratchet devices allow turning an ac input signal into a dc output signal. A ratchet device is set by moving particles driven by zero averages forces on asymmetric potentials. Hybrid nanostructures combining artificially fabricated spin ice nanomagnet arrays with superconducting films have been identified as a good choice to develop ratchet nanodevices. In the current device, the asymmetric potentials are provided by charged Néel walls located in the vertices of spin ice magnetic honeycomb array, whereas the role of moving particles is played by superconducting vortices. We have experimentally obtained ratchet effect for different spin ice I configurations and for vortex lattice moving parallel or perpendicular to magnetic easy axes. Remarkably, the ratchet magnitudes are similar in all the experimental runs; i. e. different spin ice I configurations and in both relevant directions of the vortex lattice motion. We have simulated the interplay between vortex motion directions and a single asymmetric potential. It turns out vortices interact with uneven asymmetric potentials, since they move with trajectories crossing charged Néel walls with different orientations. Moreover, we have found out the asymmetric pair potentials which generate the local ratchet effect. In this rocking ratchet the particles (vortices) on the move are interacting each other (vortex lattice); therefore, the ratchet local effect turns into a global macroscopic effect. In summary, this ratchet device benefits from interacting particles moving in robust and topological protected type I spin ice landscapes., This work was supported by Spanish MICINN grants FIS2016-76058 (AEI/FEDER, UE), EU COST- CA16218. IMDEA Nanociencia acknowledges support from the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (MICINN, Grant SEV-2016-0686). MCO and AG acknowledges financial support from Spanish MICINN Grant ESP2017-86582-C4-1-R and IJCI-2017-33991; AMN acknowledges financial support from Spanish CAM Grant 2018-T1/IND-10360. MV acknowledges financial support from Spanish MICINN Grant PID2019-104604RB/AEI/10.13039/50110001103.
- Published
- 2021
21. Vortex dynamics controlled by local superconducting enhancement
- Author
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V Rollano, A Gomez, A Muñoz-Noval, J del Valle, M Menghini, M C de Ory, J L Prieto, E Navarro, E M Gonzalez, and J L Vicent
- Subjects
superconductivity ,nanostructures ,vortices ,Science ,Physics ,QC1-999 - Abstract
A controlled local enhancement of superconductivity yields unexpected modifications in the vortex dynamics. This local enhancement has been achieved by designing an array of superconducting Nb nanostructures embedded in a V superconducting film. The most remarkable findings are: (i) vanishing of the main commensurability effect between the vortex lattice and the array unit cell, (ii) hysteretic behavior in the vortex dynamics, (iii) broadening of the vortex liquid phase and (iv) strong softening of the vortex lattice. These effects can be controlled and they can be quenched by reducing the Nb array superconducting performance applying an in-plane magnetic field. These results can be explained by taking into account the repulsive potential landscape created by the superconducting Nb nanostructures on which vortices move.
- Published
- 2019
- Full Text
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22. Visible Light Assisted Organosilane Assembly on Mesoporous Silicon Films and Particles
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Chloé Rodriguez, Alvaro Muñoz Noval, Vicente Torres-Costa, Giacomo Ceccone, and Miguel Manso Silván
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porous silicon ,visible light assisted organosilanization ,solid state NMR ,XPS ,ToF-SIMS ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Porous silicon (PSi) is a versatile matrix with tailorable surface reactivity, which allows the processing of a range of multifunctional films and particles. The biomedical applications of PSi often require a surface capping with organic functionalities. This work shows that visible light can be used to catalyze the assembly of organosilanes on the PSi, as demonstrated with two organosilanes: aminopropyl-triethoxy-silane and perfluorodecyl-triethoxy-silane. We studied the process related to PSi films (PSiFs), which were characterized by X-ray photoelectron spectroscopy (XPS), time of flight secondary ion mass spectroscopy (ToF-SIMS) and field emission scanning electron microscopy (FESEM) before and after a plasma patterning process. The analyses confirmed the surface oxidation and the anchorage of the organosilane backbone. We further highlighted the surface analytical potential of 13C, 19F and 29Si solid-state NMR (SS-NMR) as compared to Fourier transformed infrared spectroscopy (FTIR) in the characterization of functionalized PSi particles (PSiPs). The reduced invasiveness of the organosilanization regarding the PSiPs morphology was confirmed using transmission electron microscopy (TEM) and FESEM. Relevantly, the results obtained on PSiPs complemented those obtained on PSiFs. SS-NMR suggests a number of siloxane bonds between the organosilane and the PSiPs, which does not reach levels of maximum heterogeneous condensation, while ToF-SIMS suggested a certain degree of organosilane polymerization. Additionally, differences among the carbons in the organic (non-hydrolyzable) functionalizing groups are identified, especially in the case of the perfluorodecyl group. The spectroscopic characterization was used to propose a mechanism for the visible light activation of the organosilane assembly, which is based on the initial photoactivated oxidation of the PSi matrix.
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- 2019
- Full Text
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23. Design and characterization of biofunctional magnetic porous silicon flakes
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Muñoz Noval, A., García, R., Ruiz Casas, D., Losada Bayo, D., Sánchez Vaquero, V., Torres Costa, V., Martín Palma, R.J., García, M.A., García Ruiz, J.P., Serrano Olmedo, J.J., Muñoz Negrete, J.F., del Pozo Guerrero, F., and Manso Silván, M.
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- 2013
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24. Photoactivated Nanoscale Temperature Gradient Detection Using X-ray Absorption Spectroscopy as a Direct Nanothermometry Method
- Author
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Julio Camarero, Carlo Castellano, Ana Espinosa, Javier Reguera, Javier Castillo, Álvaro Muñoz-Noval, Claire Wilhelm, Germán R. Castro, Miguel A. García, Matière et Systèmes Complexes (MSC (UMR_7057)), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire Physico-Chimie Curie [Institut Curie] (PCC), and Institut Curie [Paris]-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
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Materials science ,Absorption spectroscopy ,Nanoparticle ,Bioengineering ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,law ,General Materials Science ,Nanoscopic scale ,ComputingMilieux_MISCELLANEOUS ,[PHYS]Physics [physics] ,X-ray absorption spectroscopy ,business.industry ,Lasers ,Mechanical Engineering ,Temperature ,Hyperthermia, Induced ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Laser ,0104 chemical sciences ,Photoexcitation ,Temperature gradient ,X-Ray Absorption Spectroscopy ,Nanocrystal ,Nanoparticles ,Optoelectronics ,Gold ,0210 nano-technology ,business - Abstract
Nanoparticle-mediated thermal treatments have demonstrated high efficacy and versatility as a local anticancer strategy beyond traditional global hyperthermia. Nanoparticles act as heating generators that can trigger therapeutic responses at both the cell and tissue level. In some cases, treatment happens in the absence of a global temperature rise, damaging the tumor cells even more selectively than other nanotherapeutic strategies. The precise determination of the local temperature in the vicinity of such nanoheaters then stands at the heart of thermal approaches to better adjust the therapeutic thermal onset and reduce potential toxicity-related aspects. Herein, we describe an experimental procedure by X-ray absorption spectroscopy, which directly and accurately infers the local temperature of gold-based nanoparticles, single and hybrid nanocrystals, upon laser photoexcitation, revealing significant nanothermal gradients. Such nanothermometric methodology based on the temperature-dependency of atomic parameters of nanoparticles can be extended to any nanosystem upon remote hyperthermal conditions.
- Published
- 2020
25. A combined micro-Raman, X-ray absorption and magnetic study to follow the glycerol-assisted growth of epsilon-iron oxide sol-gel coatings
- Author
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Noemi Carmona, Aida Serrano, Mariona Cabero, Germán R. Castro, Adolfo del Campo, Jesús López-Sánchez, M. Abuín, Álvaro Muñoz-Noval, Maria Varela, Oscar Rodríguez de la Fuente, Juan Rubio-Zuazo, Eduardo Salas-Colera, Comunidad de Madrid, Ministerio de Ciencia e Innovación (España), Consejo Superior de Investigaciones Científicas (España), and Agencia Estatal de Investigación (España)
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Materials science ,Absorption spectroscopy ,Iron oxide ,Nanoparticle ,chemistry.chemical_compound ,symbols.namesake ,Microscopy ,Materials Chemistry ,Sol-gel ,Materiales ,Física de materiales ,Mechanical Engineering ,Metals and Alloys ,Magnetism ,X-ray absorption spectroscopy ,Física ,Confocal Raman microscopy ,Epsilon iron oxide ,chemistry ,Chemical engineering ,Mechanics of Materials ,Sol-gel Method ,Física del estado sólido ,symbols ,Nanometre ,Absorption (chemistry) ,Raman spectroscopy ,Glycerol as a steric agent ,Sol-gel method - Abstract
[EN] Epsilon iron oxide (ε-FeO) coatings on Si(100) substrates are obtained by an easy one-pot sol-gel recipe assisted by glycerol in an acid medium. Glycerol, given its small dimensions, enables the formation of ε-FeO nanoparticles with a size of a few nanometers and the highest purity is reached in coatings after a densification treatment at 960 °C. The structural and compositional evolution up to 1200 °C is studied by confocal Raman microscopy and X-ray absorption spectroscopy techniques, correlating the existing magnetic properties. We report a novel characterization method, which allows monitoring the evolution of the precursor micelles as well as the intermediate and final phases formed. Furthermore, the inherent industrial technology transfer of the sol-gel process is also demonstrated with the ε-FeO polymorph, impelling its application in the coatings form., This work has been supported by the Ministerio de Ciencia e Innovación (MCINN, Spain) through the projects PIE: 2021-60-E-030, PIE: 2010-6-OE-013, PID2019-104717RB-I00 (2020–2022), MAT2017-86540-C4-1-R, RTI2018-095856-B-C21 (2019–2021), RTI2018-097895-B-C43 and RTI2018-095303-A-C52. The authors are grateful to The ESRF (France), MCINN and Consejo Superior de Investigaciones Científicas (CSIC, Spain) for the provision of synchrotron radiation facilities and to the BM25-SpLine Staff for their valuable help. A.S.and A.M.-N acknowledge financial support from Comunidad de Madrid (Spain) for an “Atracción de Talento Investigador” Contract 2017-t2/IND5395 and 2018-T1/IND-10360, respectively
- Published
- 2022
26. Cyclic Calcium Phosphate Electrodeposition on Porous Silicon
- Author
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Hernández-Montelongo, J., Muñoz-Noval, A., Torres-Costa, V., Martín-Palma, R.J., and Manso-Silvan, M.
- Published
- 2012
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27. Unveiling the Different Physical Origins of Magnetic Anisotropy and Magnetoelasticity in Ga-Rich FeGa Thin Films
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A. Begué, Rocío Ranchal, Álvaro Muñoz-Noval, M. Ciria, P. Bartolomé, Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), Gobierno de Aragón, Comunidad de Madrid, European Commission, and Universidad Complutense de Madrid
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Cantilever ,Materials science ,Condensed matter physics ,Absorption spectroscopy ,Física de materiales ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Condensed Matter::Materials Science ,Magnetic anisotropy ,Tetragonal crystal system ,General Energy ,Sputtering ,Distortion ,Física del estado sólido ,Physical and Theoretical Chemistry ,Thin film ,0210 nano-technology ,Anisotropy - Abstract
The aim of this work is to clarify how in-plane magnetic anisotropy and magnetoelasticity depend on the thickness of Ga-rich FeGa layers. Samples with an Fe72Ga28 composition were grown by sputtering in the ballistic regime in oblique incidence. Although for these growth conditions uniaxial magnetic anisotropy could be expected, in-plane anisotropy is only present when the sample thickness is above 100 nm. By means of differential X-ray absorption spectroscopy, we have determined the influence of both Ga pairs and tetragonal cell distortion on the evolution of the magnetic anisotropy with the increase of FeGa thickness. On the other hand, we have used the cantilever beam technique with capacitive detection to also determine the evolution of the magnetoelastic parameters with the thickness increase. In this case, experimental results can be understood considering the grain distribution. Therefore, the different physical origins for anisotropy and magnetoelasticity open up the possibility to independently tune these two characteristics in Ga-rich FeGa films., This work has been financially supported through the projects MAT2015-66888-C3-3-R and MAT2015-66726-R (MINECO/FEDER) of the Spanish Ministry of Economy and Competitiveness, RTI2018-097895-B-C43 of the Spanish Ministry of Science, Innovation, and Universities, and Gobierno de Aragón (Grant E10-17D) and Fondo Social Europeo. A.M.-N. is thankful for the contract from Universidad Complutense and Comunidad de Madrid “Atracción de Talento” program 2018-T1/IND-10360, and A.B. thanks MINECO for the Ph.D. grant BES-2016-076482.
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- 2020
28. Engineering of silicon surfaces at the micro- and nanoscales for cell adhesion and migration control
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Torres-Costa V, Martínez-Muñoz G, Sánchez-Vaquero V, Muñoz-Noval A, González-Méndez L, Punzón-Quijorna E, Gallach-Pérez D, Manso-Silván M, Climent-Font A, García-Ruiz JP, and Martín-Palma RJ
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Medicine (General) ,R5-920 - Abstract
Vicente Torres-Costa1, Gonzalo Martínez-Muñoz2, Vanessa Sánchez-Vaquero3, Álvaro Muñoz-Noval1, Laura González-Méndez3, Esther Punzón-Quijorna1,4, Darío Gallach-Pérez1, Miguel Manso-Silván1, Aurelio Climent-Font1,4, Josefa P García-Ruiz3, Raúl J Martín-Palma11Department of Applied Physics, 2Department of Computer Science, 3Department of Molecular Biology, 4Centre for Micro Analysis of Materials, Universidad Autónoma de Madrid, Madrid, SpainAbstract: The engineering of surface patterns is a powerful tool for analyzing cellular communication factors involved in the processes of adhesion, migration, and expansion, which can have a notable impact on therapeutic applications including tissue engineering. In this regard, the main objective of this research was to fabricate patterned and textured surfaces at micron- and nanoscale levels, respectively, with very different chemical and topographic characteristics to control cell–substrate interactions. For this task, one-dimensional (1-D) and two-dimensional (2-D) patterns combining silicon and nanostructured porous silicon were engineered by ion beam irradiation and subsequent electrochemical etch. The experimental results show that under the influence of chemical and morphological stimuli, human mesenchymal stem cells polarize and move directionally toward or away from the particular stimulus. Furthermore, a computational model was developed aiming at understanding cell behavior by reproducing the surface distribution and migration of human mesenchymal stem cells observed experimentally.Keywords: surface patterns, silicon, hMSCs, ion-beam patterning
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- 2012
29. Gold Nanostructures for Surface-Enhanced Raman Spectroscopy, Prepared by Electrodeposition in Porous Silicon
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Yukio H. Ogata, Raúl J. Martín-Palma, Tetsuo Sakka, Miguel Manso-Silván, Álvaro Muñoz Noval, Kazuhiro Fukami, Mohamed L. Chourou, and Ryohei Miyagawa
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gold ,electrodeposition ,porous silicon ,Raman spectroscopy ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Electrodeposition of gold into porous silicon was investigated. In the present study, porous silicon with ~100 nm in pore diameter, so-called medium-sized pores, was used as template electrode for gold electrodeposition. The growth behavior of gold deposits was studied by scanning electron microscope observation of the gold deposited porous silicon. Gold nanorod arrays with different rod lengths were prepared, and their surface-enhanced Raman scattering properties were investigated. We found that the absorption peak due to the surface plasmon resonance can be tuned by changing the length of the nanorods. The optimum length of the gold nanorods was ~600 nm for surface-enhanced Raman spectroscopy using a He-Ne laser. The reason why the optimum length of the gold nanorods was 600 nm was discussed by considering the relationship between the absorption peak of surface plasmon resonance and the wavelength of the incident laser for Raman scattering.
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- 2011
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30. Local disorder and structure relation induced by magnetic exchange interactions in A_2(Mo_(1-y)Mn_y)_2O_7 pyrochlores
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G. Lamura, Francesco Demartin, Álvaro Muñoz-Noval, Samuele Sanna, M. R. Cimberle, Giulia Berti, Marco Scavini, Carlo Castellano, Fernando Rubio-Marcos, Eduardo Salas-Colera, Castellano C., Scavini M., Berti G., Rubio-Marcos F., Lamura G., Sanna S., Salas-Colera E., Munoz-Noval A.-N., Cimberle M.R., Demartin F., and Agencia Estatal de Investigación (España)
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Materials science ,media_common.quotation_subject ,C. Order-disorder effect ,Shell (structure) ,Frustration ,Order-disorder effects ,02 engineering and technology ,C. Exchange and superexchange ,010402 general chemistry ,01 natural sciences ,Exchange and superexchange ,Distortion ,Lattice (order) ,Materials Chemistry ,media_common ,Exafs ,Materiales ,Condensed matter physics ,Oxide materials ,Física de materiales ,Mechanical Engineering ,Metals and Alloys ,D. X-ray diffraction ,021001 nanoscience & nanotechnology ,A. Oxide material ,X-ray diffraction ,0104 chemical sciences ,Ferromagnetism ,Octahedron ,Mechanics of Materials ,Superexchange ,Física del estado sólido ,Absorption (chemistry) ,0210 nano-technology ,D. EXAFS - Abstract
We present an extended X-ray absorption fine structure study at the Mo K-edge of A2(Mo1yMny)2O7 (A Gd, Ho; y 0.05 and 0.10) pyrochlores, as a function of temperature and composition, coupled to diffractometric and magnetic characterizations. Extending the study reported in our previous paper on the pristine A2Mo2O7 compounds to these Mo/Mn partially substituted samples, where we hypothesize a competition between double-exchange and superexchange couplings, we aim to check which structure parameters are related to the nature of the nearest-neighbor magnetic interactions, looking for the presence and evolution of order and structure anomalies. Two Ho samples Ho2(Mo1yMny)2O7 (y 0.05 and 0.10) keep the spin-glass nature of the parent compositions with a strong distortion of the MoO(1)6 octahedron and of the MoHo and MoMo second shell. On the other hand, two Gd2(Mo1yMny)2O7 samples, ferromagnetic at low temperature in the undoped case, show the appearance on a local scale of a spin-glass transition mirrored by a quite high structure disorder and by a distortion coherent with a lattice frustration after Mn-doping. Therefore, the Gd and Ho Mn-doped samples display a similar frustrated behavior, differently from the corresponding undoped ones. We gratefully acknowledge the Spanish CRG at the ESRF for providing beamtime under experiment HC-3343. MS thanks Prof. Monica Dapiaggi for useful discussions. GL thanks Prof. Fabio M. Canepa for illuminating discussions. F.R.-M. gratefully acknowledge the support of the AEI (Spanish Government) Project (No. MAT2017-86450-C4-1-R). F.R.-M. is indebted to MINECO for the Ramon y Cajal contract (Ref: RyC-2015-18626), which is co-financed by the European Social Fund.
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- 2021
31. Realization of macroscopic ratchet effect based on nonperiodic and uneven potentials
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Rollano, V., primary, Gomez, A., additional, Muñoz-Noval, A., additional, Velez, M., additional, de Ory, M. C., additional, Menghini, M., additional, Gonzalez, E. M., additional, and Vicent, J. L., additional
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- 2021
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32. Remaining structural capacity of concrete beams with localized corrosion of the embedded reinforcing steel
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A. A. Torres-Acosta, M. Martínez-Madrid, and A. Muñoz-Noval
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cracking ,flexure load capacity ,reinforced concrete ,accelerated corrosion ,concrete durability ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
This work presents an experimental investigation which correlates the flexure load capacity loss of reinforced concrete beams with the amount of steel cross section loss due to localized corrosion of the embedded steel. Concrete beams (100x150x1500 mm) with the central portion contaminated by chlorides, placed during mixing of the concrete, were used in this investigation. By applying a 200 µA/cm2 constant anodic current for approximately 48 to 183 days, further acceleration of the corrosion process was achieved. After the corrosion-acceleration period was over, the specimens were tested in flexure under three-point loading. In addition, the average corrosion penetration, χAVER* estimated for each corroded beam from gravimetric metal loss. The results obtained show a decrease as high as 20% in the flexure load capacity values from the localized corroded specimens with only 14% of re bar radius loss.
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- 2003
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33. In situ semi-quantitative analysis of zinc dissolution within nanoporous silicon by X-ray absorption fine-structure spectroscopy employing an X-ray compatible cell
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Álvaro Muñoz-Noval, Takuya Kuruma, Akira Koyama, Shinjiro Hayakawa, and Kazuhiro Fukami
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In situ ,Nuclear and High Energy Physics ,Radiation ,Materials science ,chemistry.chemical_element ,Zinc ,Synchrotron ,law.invention ,Electrochemical cell ,X-ray absorption fine structure ,Chemical engineering ,chemistry ,law ,Spectroscopy ,Absorption (electromagnetic radiation) ,Instrumentation ,Dissolution - Abstract
The in situ study of the discharge process in a zinc-based half-cell employing a porous electrode as a structural scaffold is reported. The in situ characterization has been performed by synchrotron X-ray absorption fine-structure spectroscopy and, for this purpose, an inexpensive, simple and versatile electrochemical cell compatible with X-ray experiments has been designed and described. The experimental results reported here have been employed to semi-quantify the dissolved and undissolved zinc species during the discharge, allowing the cell feasibility to be tested and to better understand the functioning of the zinc half-cell based on porous electrodes.
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- 2019
34. Self-assembly of iron oxide precursor micelles driven by magnetic stirring time in sol–gel coatings
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Germán R. Castro, Noemi Carmona, Eduardo Salas-Colera, Pilar Marín, José F. Marco, M. Abuín, Aida Serrano, Álvaro Muñoz-Noval, Jesús López-Sánchez, A. del Campo, O. Rodríguez de la Fuente, J. de la Figuera, European Commission, Agencia Estatal de Investigación (España), Ministerio de Economía y Competitividad (España), Comunidad de Madrid, Consejo Superior de Investigaciones Científicas (España), López-Sánchez, Jesús, Serrano, Aida, Salas- Colera, Eduardo, Rodríguez-de- la-Fuente, Oscar, Ministerio de Economía, Industria y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Ministerio de Ciencia e Innovación (España), López-Sánchez, Jesús [0000-0002-2670-9347], Serrano, Aida [0000-0002-6162-0014], Salas- Colera, Eduardo [0000-0001-7812-268X], and Rodríguez-de- la-Fuente, Oscar [0000-0002-6888-459X]
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Materials science ,General Chemical Engineering ,Iron oxide ,Nanoparticle ,02 engineering and technology ,Sol–gel ,010402 general chemistry ,01 natural sciences ,Micelle ,chemistry.chemical_compound ,Pulmonary surfactant ,Sol-gel ,Física de materiales ,Física ,General Chemistry ,021001 nanoscience & nanotechnology ,Microstructure ,3. Good health ,0104 chemical sciences ,chemistry ,Chemical engineering ,Física del estado sólido ,Alkoxide ,Self-assembly ,Microstructures ,0210 nano-technology - Abstract
[EN] The purpose of this work is to fabricate self-assembled microstructures by the sol–gel method and study the morphological, structural and compositional dependence of 3-Fe2O3 nanoparticles embedded in silica when glycerol (GLY) and cetyl-trimethylammonium bromide (CTAB) are added as steric agents simultaneously. The combined action of a polyalcohol and a surfactant significantly modifies the morphology of the sample giving rise to a different microstructure in each of the studied cases (1, 3 and 7 days of magnetic stirring time). This is due to the fact that the addition of these two compounds leads to a considerable increase in gelation time as GLY can interact with the alkoxide group on the surface of the iron oxide precursor micelle and/or be incorporated into the hydrophilic chains of CTAB. This last effect causes the iron oxide precursor micelles to be interconnected forming aggregates whose size and structure depend on the magnetic stirring time of the sol–gel synthetic route. In this paper, crystalline structure, composition, purity and morphology of the sol–gel coatings densified at 960 ºC are examined. Emphasis is placed on the nominal percentage of the different iron oxides found in the samples and on the morphological and structural differences. This work implies the possibility of patterning 3-Fe2O3 nanoparticles in coatings and controlling their purity by an easy one-pot sol–gel method., Spanish Ministry of Industry, Economy and Competitiveness for financing the project MAT2015-65445-C2-1-R, MAT2017-86450-C4-1-R, MAT2015-67557-C2-1-P, by the Comunidad de Madrid S2013/MIT-2850 NANOFRONTMAG and H2020 AMPHIBIAN Project ID: 720853. The authors are also grateful to the BM25-SpLine staff for their valuable technical support beyond their duties and for the financial support from the Spanish Ministry of Science, Innovation and Universities (MICIU) and The Spanish National Research Council (CSIC) under Grant No. PIE 2010- 6OE-013, The ESRF – The European Synchrotron, MICIU and CSIC are acknowledged for provision of synchrotron radiation facilities. A. S. acknowledges the Financial support from the Comunidad de Madrid for an “Atracción de Talento Investigador” contract (No. 2017-t2/IND5395).
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- 2019
35. Differentiation of polymorphs by Ionoluminescence
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Calvo del Castillo, H., Chene, G., Dupuis, T., Deprez, N., Strivay, D., Muñoz-Noval, A., Millán Chagoyen, M.A., Beneitez, P., and Calderon, T.
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- 2009
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36. Characterization of hybrid cobalt-porous silicon systems: protective effect of the Matrix in the metal oxidation
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Muñoz-Noval, Álvaro, Gallach, Darío, García, Miguel Ángel, Ferro-Llanos, Vicente, Herrero, Pilar, Fukami, Kazuhiro, Ogata, Yukio H, Torres-Costa, Vicente, Martín-Palma, Raúl J, Ciment-Font, Aurelio, and Manso-Silván, Miguel
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- 2012
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37. Nanostructured porous silicon micropatterns as a tool for substrate-conditioned cell research
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Punzón-Quijorna, Esther, Sánchez-Vaquero, Vanessa, Muñoz-Noval, Álvaro, Pérez-Roldán, M Jesus, Martín-Palma, Raúl J, Rossi, Francois, Climent-Font, Aurelio, Manso-Silván, Miguel, Ruiz, J Predestinacion García, and Torres-Costa, Vicente
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- 2012
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38. Photoactivated Nanoscale Temperature Gradient Detection Using X-ray Absorption Spectroscopy as a Direct Nanothermometry Method
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Espinosa A., Castro G.R., Reguera J., Castellano C., Castillo J., Camarero J., Wilhelm C., García M.A., Muñoz-Noval A. and This work was supported by Comunidad de Madrid I+D+i program (Atracción de Talento project 2018-T1/IND-10360 (A.M-N.), Atracción de Talento project 2018-T1/IND-1005 (A.E.), and NANOMAGCOST project 2018/NMT-4321 and MINECO project SEV-2016-0686. A.E. also acknowledges support from the Asociación Española contra el Cáncer program (AECC Ideas Semilla 2019). J.R. is thankful for funding from the Spanish State Research Agency (AEI) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033. We acknowledge the Spanish National Research Council (CSIC) (PIE-2010-60-E013), the Spanish Ministry of Science and Innovation (MCINN), and the ESRF for financial support, provision of synchrotron radiation facilities, and BM25 personnel for technical support in using the beamline beyond their duties.
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- 2021
39. Realization of macroscopic ratchet effect based on nonperiodic and uneven potentials
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Rollano V., Gomez A., Muñoz-Noval A., Velez M., de Ory M.C., Menghini, Mariela, Gonzalez E.M., Vicent, José Luis, Rollano V., Gomez A., Muñoz-Noval A., Velez M., de Ory M.C., Menghini, Mariela, Gonzalez E.M., and Vicent, José Luis
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- 2021
40. Photoactivated Nanoscale Temperature Gradient Detection Using X-ray Absorption Spectroscopy as a Direct Nanothermometry Method
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Espinosa, Ana, Castro G.R., Reguera J., Castellano C., Castillo J., Camarero, Julio, Wilhelm C., García M.A., Muñoz-Noval A., Espinosa, Ana, Castro G.R., Reguera J., Castellano C., Castillo J., Camarero, Julio, Wilhelm C., García M.A., and Muñoz-Noval A.
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- 2021
41. Realization of macroscopic ratchet effect based on nonperiodic and uneven potentials
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Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), European Commission, Ministerio de Economía y Competitividad (España), Comunidad de Madrid, Rollano, Víctor, Gómez, Alicia, Muñoz-Noval, Alvaro, Vélez, María, Calero de Ory, Marina, Menghini, M., González, Elvira M., Vicent, J. L., Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), European Commission, Ministerio de Economía y Competitividad (España), Comunidad de Madrid, Rollano, Víctor, Gómez, Alicia, Muñoz-Noval, Alvaro, Vélez, María, Calero de Ory, Marina, Menghini, M., González, Elvira M., and Vicent, J. L.
- Abstract
Ratchet devices allow turning an ac input signal into a dc output signal. A ratchet device is set by moving particles driven by zero averages forces on asymmetric potentials. Hybrid nanostructures combining artificially fabricated spin ice nanomagnet arrays with superconducting films have been identified as a good choice to develop ratchet nanodevices. In the current device, the asymmetric potentials are provided by charged Néel walls located in the vertices of spin ice magnetic honeycomb array, whereas the role of moving particles is played by superconducting vortices. We have experimentally obtained ratchet effect for different spin ice I configurations and for vortex lattice moving parallel or perpendicular to magnetic easy axes. Remarkably, the ratchet magnitudes are similar in all the experimental runs; i. e. different spin ice I configurations and in both relevant directions of the vortex lattice motion. We have simulated the interplay between vortex motion directions and a single asymmetric potential. It turns out vortices interact with uneven asymmetric potentials, since they move with trajectories crossing charged Néel walls with different orientations. Moreover, we have found out the asymmetric pair potentials which generate the local ratchet effect. In this rocking ratchet the particles (vortices) on the move are interacting each other (vortex lattice); therefore, the ratchet local effect turns into a global macroscopic effect. In summary, this ratchet device benefits from interacting particles moving in robust and topological protected type I spin ice landscapes.
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- 2021
42. Experimental artifact in MOKE measurements when using paramagnetic sample holders
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M. A. García, A. Muñoz-Noval, C. J. Bonin, and F. Bonetto
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Artifact (error) ,MAGNETO-OPTIC KERR EFFECT ,Materials science ,Applied Mathematics ,purl.org/becyt/ford/1.3 [https] ,EXPERIMENTAL ARTIFACTS ,Sample (graphics) ,purl.org/becyt/ford/1 [https] ,Paramagnetism ,Nuclear magnetic resonance ,DATA ANALYSIS ,Magneto-optic Kerr effect ,Instrumentation ,Engineering (miscellaneous) - Abstract
We describe here an artifact that may affect to magneto-optical Kerr measurements. When paramagnetic sample holders (SH) with non-negligible susceptibilities are used, the inhomogeneity of the applied magnetic field can induce forces and torques on it, shifting the reflected beam, and altering its intensity at the photodetector. The effect is even and can be avoided using low susceptibility paramagnetic or diamagnetic SH We also present a detailed analytical description of the magnetic forces involved and provide some estimated values of the SH shifting, showing that they might distort the magneto-optical Kerr effect signal. Moreover, in this paper we show how the artifact can be removed from the experimental curves with an appropriated data analysis. Fil: Munoz-Noval, Alvaro. Comunidad de Madrid; España Fil: Bonin, Claudio Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentina Fil: Bonetto, Fernando Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentina Fil: Garcia, Miguel Angel. Institute For Ceramic And Glass; España
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- 2020
43. Little–Parks effect governed by magnetic nanostructures with out-of-plane magnetization
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Álvaro Muñoz-Noval, M. C. de Ory, Encina M González, J. L. Vicent, Ana M. Gómez, M. Menghini, V. Rollano, Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737, Centros de Excelencia Severo Ochoa, INSTITUTO MADRILEÑO DE ESTUDIOS AVANZADOS EN NANOCIENCIA, SEV-2016-0686, Muñoz Nova, A. [0000-0003-3236-5509], González, E. M. [0000-0001-9360-3596], Gómez, A. [0000-0002-8752-1401], Agencia Estatal de Investigación (AEI), Comunidad de Madrid, Spanish Government, European Cooperation in Science and Technology (COST), Spanish MICINN Grant, and Centro de Excelencia Científica Severo Ochoa IMDEA Nanociencia
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Work (thermodynamics) ,Materials science ,Field (physics) ,lcsh:Medicine ,02 engineering and technology ,Little–Parks effect ,01 natural sciences ,Article ,Magnetization ,Condensed Matter::Superconductivity ,0103 physical sciences ,lcsh:Science ,010306 general physics ,Superconductivity ,Multidisciplinary ,Condensed matter physics ,Física de materiales ,Physics ,lcsh:R ,021001 nanoscience & nanotechnology ,Magnetic field ,Vortex ,Física del estado sólido ,lcsh:Q ,Nanodot ,0210 nano-technology - Abstract
Little–Parks effect names the oscillations in the superconducting critical temperature as a function of the magnetic field. This effect is related to the geometry of the sample. In this work, we show that this effect can be enhanced and manipulated by the inclusion of magnetic nanostructures with perpendicular magnetization. These magnetic nanodots generate stray fields with enough strength to produce superconducting vortex–antivortex pairs. So that, the L–P effect deviation from the usual geometrical constrictions is due to the interplay between local magnetic stray fields and superconducting vortices. Moreover, we compare our results with a low-stray field sample (i.e. with the dots in magnetic vortex state) showing how the enhancement of the L–P effect can be explained by an increment of the effective size of the nanodots., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)
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- 2020
44. Janus Magnetic-Plasmonic Nanoparticles for Magnetically Guided and Thermally Activated Cancer Therapy
- Author
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Espinosa A., Reguera J., Curcio A., Muñoz-Noval Á., Kuttner C., Van de Walle A., Liz-Marzán L.M., Wilhelm C. and This work was supported by the European Union (Marie Curie Intra-European Project FP7-PEOPLE-2013-740 IEF-62647). A.E. acknowledges the support by Comunidad de Madrid (Talento project 2018-T1/IND-1005 and NANOMAGCOST project 2018/NMT-4321), MINECO project SEV-2016-0686, and AECC project Ideas Semilla 2019. A.M.-N. acknowledges the support by Comunidad de Madrid (Talento project 2018-T1/IND-10360). C.K. acknowledges financial support from the European Commission under the Marie Sk?odowska-Curie program (H2020-MSCA-799393, NANOBIOME). L.M.L.-M. acknowledges support from MINECO project MAT2017-86659-R and Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720). The authors are grateful to Christine P?choux for TEM preparation (INRA in Jouy-en-Josas, Paris, France), Ludovic Maingault, and Isabelle Le Parco for their help in animal studies (Jacques Monod Institute, Paris, France). The authors thank Andreas Seifert (CIC nanoGUNE) for providing access to the diffuse reflectance setup and scientific discussion. The authors acknowledge the ESRF for beamtime and the CRG beamline BM25-SpLine personnel for technical support. The authors thank for technical and human support provided by SGIker (UPV/EHU/ ERDF, EU).
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- 2020
45. Janus Magnetic‐Plasmonic Nanoparticles for Magnetically Guided and Thermally Activated Cancer Therapy
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Christian Kuttner, Álvaro Muñoz-Noval, Aurore Van de Walle, Javier Reguera, Claire Wilhelm, Luis M. Liz-Marzán, Ana Espinosa, Alberto Curcio, Matière et Systèmes Complexes (MSC (UMR_7057)), and Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
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Materials science ,Nanostructure ,[SDV]Life Sciences [q-bio] ,Nanoparticle ,Nanotechnology ,Multifunctional Nanoparticles ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Biomaterials ,Magnetics ,[SPI]Engineering Sciences [physics] ,In vivo ,Cell Line, Tumor ,Neoplasms ,[CHIM]Chemical Sciences ,General Materials Science ,Janus ,ComputingMilieux_MISCELLANEOUS ,Plasmonic nanoparticles ,Hyperthermia, Induced ,General Chemistry ,Phototherapy ,Photothermal therapy ,equipment and supplies ,021001 nanoscience & nanotechnology ,3. Good health ,0104 chemical sciences ,Magnetic Fields ,Magnetic hyperthermia ,Systemic administration ,Nanoparticles ,Gold ,0210 nano-technology ,human activities ,Biotechnology - Abstract
Progress of thermal tumor therapies and their translation into clinical practice are limited by insufficient nanoparticle concentration to release therapeutic heating at the tumor site after systemic administration. Herein, the use of Janus magneto-plasmonic nanoparticles, made of gold nanostars and iron oxide nanospheres, as efficient therapeutic nanoheaters whose on-site delivery can be improved by magnetic targeting, is proposed. Single and combined magneto- and photo-thermal heating properties of Janus nanoparticles render them as compelling heating elements, depending on the nanoparticle dose, magnetic lobe size, and milieu conditions. In cancer cells, a much more effective effect is observed for photothermia compared to magnetic hyperthermia, while combination of the two modalities into a magneto-photothermal treatment results in a synergistic cytotoxic effect in vitro. The high potential of the Janus nanoparticles for magnetic guiding confirms them to be excellent nanostructures for in vivo magnetically enhanced photothermal therapy, leading to efficient tumor growth inhibition.
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- 2020
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46. Little–Parks effect governed by magnetic nanostructures with out-of-plane magnetization
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de Ory M.C., Rollano V., Gomez A., Menghini, Mariela, Muñoz-Noval A., Gonzalez E.M., Vicent, José Luis, de Ory M.C., Rollano V., Gomez A., Menghini, Mariela, Muñoz-Noval A., Gonzalez E.M., and Vicent, José Luis
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- 2020
47. Janus Magnetic-Plasmonic Nanoparticles for Magnetically Guided and Thermally Activated Cancer Therapy
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Espinosa, Ana, Reguera J., Curcio A., Muñoz-Noval Á., Kuttner C., Van de Walle A., Liz-Marzán L.M., Wilhelm C., Espinosa, Ana, Reguera J., Curcio A., Muñoz-Noval Á., Kuttner C., Van de Walle A., Liz-Marzán L.M., and Wilhelm C.
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- 2020
48. Little–Parks effect governed by magnetic nanostructures with out-of-plane magnetization
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Calero de Ory, Marina, Rollano, V., Gómez, Alicia, Menghini, M., Muñoz-Noval, Alvaro, González, Elvira M., Vicent, J.L., Calero de Ory, Marina, Rollano, V., Gómez, Alicia, Menghini, M., Muñoz-Noval, Alvaro, González, Elvira M., and Vicent, J.L.
- Abstract
Little–Parks effect names the oscillations in the superconducting critical temperature as a function of the magnetic field. This effect is related to the geometry of the sample. In this work, we show that this effect can be enhanced and manipulated by the inclusion of magnetic nanostructures with perpendicular magnetization. These magnetic nanodots generate stray fields with enough strength to produce superconducting vortex–antivortex pairs. So that, the L–P effect deviation from the usual geometrical constrictions is due to the interplay between local magnetic stray fields and superconducting vortices. Moreover, we compare our results with a low-stray field sample (i.e. with the dots in magnetic vortex state) showing how the enhancement of the L–P effect can be explained by an increment of the effective size of the nanodots.
- Published
- 2020
49. Crystal defects and optical emissions of pulse electrodeposited ZnO
- Author
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Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Comunidad de Madrid, European Commission, Consejo Superior de Investigaciones Científicas (España), Manzano, Cristina V., Serrano Rubio, Aída, Muñoz-Noval, Alvaro, Fernández Lozano, José Francisco, Martín-González, Marisol, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Comunidad de Madrid, European Commission, Consejo Superior de Investigaciones Científicas (España), Manzano, Cristina V., Serrano Rubio, Aída, Muñoz-Noval, Alvaro, Fernández Lozano, José Francisco, and Martín-González, Marisol
- Abstract
ZnO has been widely studied in the last decades as an n-type semiconductor due to its wide application range, for example, in optoelectronics, solar cells, light-emitting diodes, thermoelectrics, amongst others. The material efficiency for certain applications is highly dependent on the presenting film morphology. Electrodeposition is well-known as a technique with precise control over the structural and morphological properties of the obtained materials. When the structural and morphological properties are tuned, it is possible to find a wide variety of defects in the ZnO structure. In this study, ZnO films were grown using pulsed electrodeposition with variation of the reduction potential. The crystal order, structural defects and optical emissions of the films have been analyzed by X-Ray Diffraction (XRD), X-ray Absorption Near-Edge Structure (XANES), Extended X-ray Absorption Fine Structure (EXAFS) and Photoluminescence (PL). ZnO film grown at less negative reduction potential presents a stronger texture along [0001] by XRD, higher crystalline order, and more zinc vacancies by XANES and EXAFS. The films obtained at less negative potential present less OH trapped in the ZnO structure and a relatively higher level of defects O, O, O and O than those grown at higher reduction potentials by PL. This will be related to the fact that at less negative potentials there is less concentration of OH at the film surface than at more negative potentials. The combination of X-ray absorption spectroscopy and photoluminescence reveals the complicated nature of the atomic defect in electrodeposited ZnO films. Allowing to evidence the preferential presence of atomic defect as a function of the reduction potential. In this work, we have also compared those defects with reference compounds such as a Zn foil and ZnO polycrystalline powder.
- Published
- 2020
50. Unveiling the different physical origins of magnetic anisotropy and magnetoelasticity in Ga-Rich FeGa thin films
- Author
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Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), Gobierno de Aragón, Comunidad de Madrid, European Commission, Universidad Complutense de Madrid, Bartolomé, P., Begué Gracia, Adrián, Muñoz-Noval, Alvaro, Ciria, Miguel, Ranchal, R., Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), Gobierno de Aragón, Comunidad de Madrid, European Commission, Universidad Complutense de Madrid, Bartolomé, P., Begué Gracia, Adrián, Muñoz-Noval, Alvaro, Ciria, Miguel, and Ranchal, R.
- Abstract
The aim of this work is to clarify how in-plane magnetic anisotropy and magnetoelasticity depend on the thickness of Ga-rich FeGa layers. Samples with an Fe72Ga28 composition were grown by sputtering in the ballistic regime in oblique incidence. Although for these growth conditions uniaxial magnetic anisotropy could be expected, in-plane anisotropy is only present when the sample thickness is above 100 nm. By means of differential X-ray absorption spectroscopy, we have determined the influence of both Ga pairs and tetragonal cell distortion on the evolution of the magnetic anisotropy with the increase of FeGa thickness. On the other hand, we have used the cantilever beam technique with capacitive detection to also determine the evolution of the magnetoelastic parameters with the thickness increase. In this case, experimental results can be understood considering the grain distribution. Therefore, the different physical origins for anisotropy and magnetoelasticity open up the possibility to independently tune these two characteristics in Ga-rich FeGa films.
- Published
- 2020
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