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The use of magnetic vector tomography/laminography has opened a 3D experimental window to access the magnetization at the nanoscale. These methods exploit the dependence of the magnetic contrast in transmission to recover its 3D configuration. However, hundreds of different angular projections are required leading to large measurement times. Here we present a fast method to dramatically reduce the experiment time specific for quasi two-dimensional magnetic systems. The algorithm uses the Beer-Lambert equation in the framework of X-ray transmission microscopy to obtain the 3D magnetic configuration of the sample. It has been demonstrated in permalloy microstructures, reconstructing the magnetization vector field with a reduced number of angular projections obtaining quantitative results. The throughput of the methodology is × 10–× 100 times faster than conventional magnetic vector tomography, making this characterization method of general interest for the community.

Bloch points are small 3D magnetic textures with unit topological charge that require the use of advanced vector imaging techniques for their direct experimental characterization. Here we show results from the reconstruction of the magnetization field m(r) of an elongated permalloy microstructure by X-ray vector magnetic tomography. A central asymmetric Bloch domain wall is observed, decorated by Bloch points arranged in several dipoles and a triplet. The analysis of the m(r) map in terms of topological concepts provides a quantitative description of the Bloch points as topological monopoles connected by bundles of emergent magnetic field lines carrying a fractional topological flux. It also reveals the topological constraints that determine chirality transitions of the central domain wall in the vicinity of Bloch points, independent of specific material properties. This approach could be readily extended to the study of magnetic microstructures in arbitrary remanent configurations.

This data set contains Magnetic Transmission X-ray Microscopy images from a permalloy microstructure acquired at MISTRAL beamline (ALBA Synchrotron) that have been used to obtain the magnetic tomograms analyzed in the research paper "Bloch points and topological dipoles observed by X-ray vector magnetic tomography in a ferromagnetic microstructure" at Communication Physics (2023).

This project analyses Virginia Woolf's perception of women and literature in her essay A Room of One's Own (1929). And it does so from the dual perspective of class and gender. Woolf's essay foregrounds the critical role of material conditions in making possible the success of any writer. However, women writers have traditionally confronted more difficulties in achieving the same recognition as their male counterparts. Woolf is known for being a pioneer of literary feminism, but this claim involves several complexities that need to be explored. Issues like social class and social prejudice are also important parts of the equation. That is why this thesis outlines the writer's views on women's literature in the course of history against social and economic factors. Ultimately, I intend to highlight the groundbreaking nature of Virginia Woolf's diachronic exploration of the discrimination suffered by women as writers: an exploration involving literary and social statements., Este trabajo analiza la percepción de las mujeres y la literatura en el ensayo Una habitación propia (1929) escrito por Virginia Woolf, y lo hace desde la doble perspectiva de clase y género. El ensayo de Woolf subraya el papel crítico de las condiciones materiales que hacen posible el éxito de cualquier escritor. Sin embargo, las escritoras tradicionalmente han enfrentado más vicisitudes para lograr el mismo reconocimiento que sus homólogos masculinos. Woolf es célebre por ser una pionera del feminismo literario, pero esta afirmación implica varias complejidades que deben explorarse. Cuestiones como la clase o el prejuicio sociales también son partes importantes de la ecuación. Por ese motivo, este trabajo de fin de grado esboza la perspectiva de la escritora en la literatura femenina a lo largo de la historia en contraste con los factores sociales y económicos. En última instancia, pretendo destacar el carácter innovador de la exploración diacrónica de Woolf sobre la discriminación que sufren las mujeres como escritoras: una exploración que implica posicionamientos literarios y sociales., Departamento de Filología Inglesa, Grado en Estudios Ingleses

Detective novels are one of the most popular literary genres in the English language. However, although several writers have contributed to this literary formula, the most prominent author is undoubtedly Agatha Mary Clarissa Christie (1890 - 1976). Christie is a best-selling crime and mystery author who is often regarded as the genre's finest exponent. This Bachelor’s Thesis is largely concerned with evaluating detective fiction, especially the subgenres of thriller and whodunit, in two of Christie’s best-known masterpieces: The Murder of Roger Ackroyd (1926) and And Then There Were None (1939). An in-depth examination of both works is provided here in order to prove the representation of both subgenres in Christie’s ouvre and to contrast their differences, as well as to determine which typology prevails in each case, Las novelas detectivescas son uno de los géneros literarios más populares en lengua inglesa. Sin embargo, aunque diferentes escritores han contribuido a este formato literario, la autora más destacada es sin duda Agatha Mary Clarissa Christie (1890 - 1976). Christie es una autora de best-sellers de crimen y misterio, considerada el mejor exponente del género. Este proyecto se encarga en gran medida de evaluar la ficción detectivesca, especialmente los subgéneros thriller y whodunit, en dos conocidas novelas de esta autora: El asesinato de Roger Ackroyd (1926) y Y no quedó ninguno (1939). Se ofrece un análisis en profundidad de ambas obras para demostrar la presencia de ambos subgéneros en la producción novelística de Agatha Christie y contrastar sus diferencias, así como para determinar qué tipología prevalece en cada caso., Departamento de Filología Inglesa, Grado en Estudios Ingleses

Analysis of the effect of damping on spin-wave dynamics; explanation of wavevector shift in dispersion relations of different magnetization components.

Reconfigurable magnetization textures offer control of spin waves with promising properties for future low-power beyond-CMOS systems. However, materials with perpendicular magnetic anisotropy (PMA) suitable for stable magnetization-texture formation are characterized by high damping, which limits their applicability in magnonic devices. Here, we propose to overcome this limitation by using hybrid structures, i.e., a PMA layer magnetostatically coupled to a low-damping soft ferromagnetic film. We experimentally show that a periodic stripe-domain texture from a PMA layer is imprinted upon the soft layer and induces a nonreciprocal dispersion relation of the spin waves confined to the low-damping film. Moreover, an asymmetric bandgap features the spin-wave band diagram, which is a clear demonstration of collective spin-wave dynamics, a property characteristic for magnonic crystals with broken time-reversal symmetry. The composite character of the hybrid structure allows for stabilization of two magnetic states at remanence, with parallel and antiparallel orientation of net magnetization in hard and soft layers. The states can be switched using a low external magnetic field; therefore, the proposed system obtains an additional functionality of state reconfigurability. This study offers a link between reconfigurable magnetization textures and low-damping spin-wave dynamics, providing an opportunity to create miniaturized, programmable, and energy-efficient signal processing devices operating at high frequencies.

Patterned elements of permalloy (Py) with a thickness as large as 300 nm have been defined by electron beam lithography on X-ray-transparent 50 nm thick membranes in order to characterize their magnetic structure via Magnetic Transmission X-ray Microscopy (MTXM). To avoid the situation where the fragility of the membranes causes them to break during the lithography process, it has been found that the spin coating of the resist must be applied in two steps. The MTXM results show that our samples have a central domain wall, as well as other types of domain walls, if the nanostructures are wide enough.

Full control of magnetic properties in exchange coupled systems requires a good understanding of 3D magnetic configuration with lateral and in-depth resolution. Here we show results from a soft X-ray tomographic reconstruction which allow determining, solely from the experimental data, a detailed description of the vector magnetic configuration of a ferrimagnetic Gd12Co88/Nd17Co83/Gd24Co76 trilayer with engineered competing anisotropy, exchange and magnetostatic interactions at different depths. The trilayer displays chevron patterns with a distorted closure structure. Near the top Gd24Co76 layer, local exchange springs with out-of-plane magnetization reversal, quasi-domains with ripple-like patterns and magnetic vortices and antivortices across the thickness are observed. The detailed analysis of the magnetic tomogram shows that the effective strength of the exchange spring at the NdCo/GdCo interface can be finely tuned by GdxCo1-x composition and anisotropy (determined by sample fabrication) and in-plane stripe orientation (adjustable), demonstrating the suitability of 3D magnetic visualization techniques in magnetic engineering research.

Given the relevance of textual interpretation for the task of the literary translator, it could be argued that such an ambiguous work like Henry James’s The Turn of the Screw is especially problematic. The translator of the work must convey the same message as the original author intended, as well as the style characterizing the source; however, in the case of this nineteenth-century classic this message is not any clearer than the tale’s nature itself. Nearly a century of debate on the reliability of the novella’s narrator has not yielded definitive conclusions. The present graduate thesis undertakes the comparison of two Spanish translations of James’s work so as to assess the extent to which the translator’s personal interpretations mould their respective versions by making them more univocal than the source text; or if, conversely, being aware of the narrative’s ambiguity, the translators succeed in retaining the original’s deliberate obscurity., Dada la relevancia de la interpretación textual para la tarea de un traductor literario, se podría argumentar que una obra tan ambigua como Otra vuelta de tuerca de Henry James resulta especialmente problemática. El traductor debe transmitir el mismo mensaje del texto fuente con el mismo estilo; sin embargo, en el caso de este clásico del siglo XIX, ni este mensaje ni la naturaleza del relato están claros. Casi un siglo de debate sobre la fiabilidad de la narradora de la novela no ha arrojado conclusiones definitivas. El presente Trabajo de Fin de Grado aborda la comparación de dos traducciones españolas de la novella de James con el fin de evaluar en qué medida las interpretaciones personales de los traductores moldean sus respectivas versiones haciéndolas más unívocas que el texto fuente; o si, por el contrario, los traductores, conscientes de la ambigüedad de la obra, logran mantener la deliberada oscuridad del original., Departamento de Filología Inglesa, Grado en Estudios Ingleses

This graduation project attempts to suggest the potential of implementing a perspective on literary criticism of narrative works that draws upon some notions from Abraham Maslow’s theory of human motivation and adopts some of its terminology. More particularly, the focus lies on the use of interrogative clauses in character dialogue and the importance of motivation itself in character construction and development. Illustrations from several canonical literary works will be provided so as to rehearse this mode of textual analysis, which we believe can provide a potentially useful framework to approach narrative fiction from the point of view of humanistic psychology., El presente TFG busca sugerir el potencial de implementar una modalidad de crítica literaria aplicada a obras narrativas que se basa en varias nociones de la teoría de la motivación humana formulada por Abraham Maslow, cuya terminología se adopta parcialmente. Concretamente, nos centraremos en el uso de oraciones interrogativas en los diálogos de los personajes y en la importancia de la motivación en sí misma para la configuración y el desarrollo de dichos personajes. Se proporcionarán ilustraciones extraídas de varias obras literarias canónicas para ensayar este modo de análisis textual, que creemos puede proporcionar un marco potencialmente útil en el abordaje de la ficción narrativa desde el punto de vista de la psicología humanista., Departamento de Filología Inglesa, Grado en Estudios Ingleses

In plane magnetization stripes of soft magnetic alloys have been proposed as magnetic information storage devices. In these kind of systems, regions of uniform magnetization with opposite senses are separated by domain walls(DW), known as head-to-headortail-to-tail walls, that may have different structures depending on the width and thickness of the stripes. Usually, two types of DW are expected, known as transverse, for thin stripes, orvortex, for thick stripes. The work by Nguyenetal has shown that in stripes thicker than 60nm, a thirdty peofhead-to-head DWmay exist, the so called Landauwall, with a significantout-of-plane magnetization core that is not homogenous across the film thickness.

Very recently magnetic stripe domains, characterized by alternating up and down out-of-plane orientation of the magnetization, have received great interest due to the possibility to use stripe patterns to manipulate spin-wave (SW) propagation as in artificial magnonic crystals. In this work, we demonstrate the control of the SW propagation by using reconfigurable regular stripe-pattern domain structure in the hybrid system. The investigated system consists of 64-nm-thick NdCo layer and 10-nm-thick NiFe layer, coupled through an Al layer of different thicknesses. Magnetic force microscopy (MFM) measurements show that, due to the perpendicular magnetic anisotropy of the NdCo film, the system develops stripe domains aligned with the last in-plane saturation direction. The domain pattern is found to have a period of about 140 nm, which is almost independent on the thickness of the Al layer. The magnetization reversal of the trilayer system was investigated by vibrating sample magnetometer, showing that the hysteresis loop is characterized by a two-step process, due to the different coercivity of the NiFe and NdCo films. Detailed analysis of the hysteresis loops along with micromagnetic simulations indicates that the stray magnetic field coming from the NdCo layer induces a regular domain structure also in the NiFe layer, which is tuned by the thickness of Al spacer. In addition, upon reversing the applied magnetic field, an antiparallel state, characterized by an antiparallel alignment of the magnetization component parallel to the domain axis in the NdCo and NiFe stripes, is formed. Then, Brillouin light scattering spectroscopy has been used to measure the spectra of the SWs propagating in the direction perpendicular to stripe domains for the parallel and the antiparallel state. For both configurations, the dispersion relation shows a strongly nonreciprocal mode. However, in the parallel state SWs propagating with positive and negative wavevector are both characterized