The electronic, lattice dynamical, electron-phonon coupling, and superconducting properties of alkali-metal hydrides LiH, NaH, and KH, metalized through doping with alkaline-earth metals Be, Mg, and Ca, respectively, are investigated within the framework of density functional perturbation theory. The alloys were modeled by the self-consistent virtual crystal approximation, and the effect of zero-point energy contribution is consistently taken into account. For all three alloys, a steady increase of the electron-phonon coupling constant $\lambda$ is found with progressive alkaline-earth metal doping, reaching values as high as 0.47 for (Li/Be)H, 1.26 for (Na/Mg)H, and 1.69 for (K/Ca)H. The growth of $\lambda$ with doping is the result of two effects: the softening of the phonon spectrum, mainly of the H-optical modes, and the increase of the density of states at the Fermi level. Estimates of the superconducting critical temperature reach values of 2.1 K for ${\mathrm{Li}}_{0.95}{\mathrm{Be}}_{0.05}\mathrm{H}$, 28 K for ${\mathrm{Na}}_{0.8}{\mathrm{Mg}}_{0.2}\mathrm{H}$, and even 49 K for ${\mathrm{K}}_{0.55}{\mathrm{Ca}}_{0.45}\mathrm{H}$, demonstrating that doping is an alternative route to high transition temperatures in this material class without the need to apply high external pressure.

The structural, electronic, lattice dynamics, electron–phonon (el–ph) coupling, and superconducting (SC) properties of the alkali-metal hydride RbH, metallized through electron-doping by the construction of the solid-solution Rb 1 − x Sr _x H, are systematically analyzed as a function of Sr-content within the framework of density functional perturbation and Migdal-Eliashberg theories, taking into account the effect of zero-point energy contribution by the quasi-harmonic approximation. For the entire studied range of Sr-content, steady increments of the el–ph coupling constant and the SC critical temperature are found with progressive alkaline-earth metal content through electron-doping, reaching the values of λ = 1.92 and T c = 51.3 ( 66.1 ) K with μ ∗ = 0.1(0). The steady rise of such quantities as a function of Sr-content is consequence of the metallization of the hydride as an increase of density of states at the Fermi level is observed, as well as the softening of the phonon spectrum, mainly coming from H-optical modes. Our results indicate that electron-doping on metal-hydrides is an encouraging alternative to look for superconductivity without applied pressure.

Transition metal nitrides are well-known 3D superconductor materials. However, there is a lack of knowledge related to their two-dimensional (2D) counterparts, which have several potential technological applications. In this work, we predict, using an evolutionary algorithm coupled with a first-principles approach, a set of novel 2D superconductive structures based on tungsten nitride. Through a systematic process including energetic and dynamical analysis, three thermodynamically stable compositions along with metastable compounds were studied in the following stoichiometries: W₄N₂, W₂N₂, and W₂N₃. Their superconductive temperature ( T c ) values, estimated by means of the Eliashberg superconductive theory and the McMillan equation, range from 2.3 to 21.6 K, where the highest T c value corresponds to a W₂N₃ metastable hexagonal system. A systematic analysis of the structural, electronic, vibrational and electron–phonon (e–ph) properties, allowed us to recognize the variables that modulate the T c in theses systems. The superconductive behavior is strongly affected by changes in the nitrogen density of states at Fermi level, the e–ph coupling constant and the lattice symmetry. The present results aim to encourage further theoretical and experimental efforts over non fully explored superconductors in two dimensions.

El proyecto de “Jardín sensorial inclusión y bienestar para todos de la mano de la BUAP (VIEP-BUAP 2024:24073 Bioinformática inclusiva). Tiene como objetivo diseñar un símbolo de identidad, que además de englobar el mensaje de respeto hacia nuestro medio ambiente, también abrace e invite a las personas de baja visión y/o ciegas a interactuar en este jardín. Para lograr este objetivo se emplearon softwares de diseño y de dibujo, además se realizó una revisión en la literatura científica para identificar los colores que se han asociado a las emociones universales, enraizadas en el pensamiento humano; de los cuales se buscaron los más apropiados para transmitir el mensaje de forma efectiva en todos los elementos gráficos que conforman la identidad visual. A partir de esta investigación se desarrolló el proceso creativo que constó de la edición del isologo y la justificación de la implementación de cada uno de los elementos que lo conforman. Finalmente se presenta el isologo en dos trípticos y una infografía digital que divulgan la importancia y utilidad del compostaje, así como el proceso para realizar figuras de yeso, las cuales pueden ser incorporadas a los jardines para que la planta obtenga una fuente de calcio permanente.