Física y género: el Proyecto “Diversity in The Cultures of Physics”

Una educación en Ciencias Físicas abre un notable abanico de posibilidades de carrera profesional; sin embargo, estas oportunidades no están igualmente disponibles para todos a causa de que los grupos subrepresentados entre el estudiantado y el corpus de profesionales de la Física y los campos relacionados, especialmente las mujeres, acaban teniendo un acceso limitado a los recursos que deberían permitirles desarrollar plenamente su potencial. Con ligeras variaciones, este es el caso en toda el área de investigación europea. En el presente trabajo presentaremos un análisis del proyecto Erasmus+ “Diversity in the Cultures of Physics”, centrado en acompañar y apoyar a las mujeres que están al final de sus estudios de Física (o al inicio de sus doctorados) para que accedan en el futuro a la investigación y a la enseñanza, a la innovación, a la industria, conscientes de los sesgos de género que deben afrontar e, idealmente, con las herramientas que les permitan sortearlosAn education in physics offers a remarkable diversity of career options; however, these opportunities are not equally open to all because underrepresented groups within the students and scientists in physics and related fields, most notably women, are granted only limited access to fully realize their individual potentials. With only slight variations, this is the case across the European research area. In the present work we will undertake an analysis of the Erasmus+ project "Diversity in the Cultures of Physics", focused on coaching and supporting women who are at the end of their physics degrees (or at the beginning of their PhDs) so that they can, in the future, get an access to research and teaching, to innovation, to industry, well aware of the gender biases they are to face and, ideally, having the tools to overcome them

Mujeres en física: identidad profesional y persistencia de la anomalía

[ES] En este articulo se abordan las dificultades de las mujeres jóvenes para verse haciendo física, así como las diferencias en la identidad profesional de hombres y mujeres en física, y las violencias simbólicas que nos atraviesan a las mujeres en este campo. Esto nos lleva a interrogarnos sobre la cultura profesional en la que nos desempeñamos, y sobre cómo nos afecta trabajar en un campo tan masculinizado donde, en consecuencia, es más difícil colaborar con otras mujeres. Partiendo de estos análisis valoramos en clave género los cambios que se están dando en los últimos años, en los que la física en España se está volviendo cada vez más neoliberal

L’anomalia d’una dona en la física

Traducció a cura de Sònia Estradé de l'article d'Evelyn Fox Keller de 197

Mapping the magnetic coupling of self-assembled Fe3O4 nanocubes by electron holography

The nanoscale magnetic configuration of self-assembled groups of magnetite 40 nm cubic nanoparticles has been investigated by means of electron holography in the transmission electron microscope (TEM). The arrangement of the cubes in the form of chains driven by the alignment of their dipoles of single nanocubes is assessed by the measured in-plane magnetic induction maps, in good agreement with theoretical calculations

Comparative of machine learning classification strategies for electron energy loss spectroscopy: Support vector machines and artificial neural networks

Machine Learning (ML) strategies applied to Scanning and conventional Transmission Electron Microscopy have become a valuable tool for analyzing the large volumes of data generated by various S/TEM techniques. In this work, we focus on Electron Energy Loss Spectroscopy (EELS) and study two ML techniques for classifying spectra in detail: Support Vector Machines (SVM) and Artificial Neural Networks (ANN). Firstly, we systematically analyze the optimal configurations and architectures for ANN classifiers using random search and the tree-structured Parzen estimator methods. Secondly, a new kernel strategy is introduced for the soft-margin SVMs, the cosine kernel, which offers a significant advantage over the previously studied kernels and other ML classification strategies. This kernel allows us to bypass the normalization of EEL spectra, achieving accurate classification. This result is highly relevant for the EELS community since we also assess the impact of common normalization techniques on our spectra using Uniform Manifold Approximation and Projection (UMAP), revealing a strong bias introduced in the spectra once normalized. In order to evaluate and study both classification strategies, we focus on determining the oxidation state of transition metals through their EEL spectra, examining which feature is more suitable for oxidation state classification: the oxygen K peak or the transition metal white lines. Subsequently, we compare the resistance to energy loss shifts for both classifiers and present a strategy to improve their resistance. The results of this study suggest the use of soft-margin SVMs for simpler EELS classification tasks with a limited number of spectra, as they provide performance comparable to ANNs while requiring lower computational resources and reduced training times. Conversely, ANNs are better suited for handling complex classification problems with extensive training data

Nucleation and growth of GaN nanorods on Si (111) surfaces by plasma-assisted molecular beam epitaxy - The influence of Si- and Mg-doping

The self-assembled growth of GaN nanorods on Si (111) substrates by plasma-assisted molecular beam epitaxy under nitrogen-rich conditions is investigated. An amorphous silicon nitride layer is formed in the initial stage of growth that prevents the formation of a GaN wetting layer. The nucleation time was found to be strongly influenced by the substrate temperature and was more than 30 min for the applied growth conditions. The observed tapering and reduced length of silicon-doped nanorods is explained by enhanced nucleation on nonpolar facets and proves Ga-adatom diffusion on nanorod sidewalls as one contribution to the axial growth. The presence of Mg leads to an increased radial growth rate with a simultaneous decrease of the nanorod length and reduces the nucleation time for high Mg concentrations