Year 1 timetable

Title: Magnetostructural properties of materials at finite temperature by means of magnetically constrained supercell calculations

Speaker: Eduardo Mendive Tapia

Abstract: Caloric refrigeration offers an environmentally friendly alternative to conventional cooling technologies that rely on greenhouse gas-emitting refrigerants, by instead using solid-state materials. Fundamental research in this area focuses on first-order (discontinuous) magnetic phase transitions, which produce large cooling responses near the transition point [1]. However, accurately describing these transitions from first principles is a major challenge due to the need to appropriately capture finite-temperature effects. In this presentation, a first-principles approach for computing the temperature-dependent properties of magnetic materials by means of magnetically constrained supercell calculations [2] will be presented. This method efficiently samples thermal fluctuations of disordered local moments [3], enabling a realistic treatment of temperature-dependent magnetism and revealing how electronic and magnetovolume interactions drive their first-order character. The approach will be illustrated with several case studies, including body-centered cubic iron (bcc Fe), triangular antiferromagnets Mn₃AN (A = Ga, Ni) in the antiperovskite structure [2], and van der Waals ferromagnets [4]. Future extensions and applications will be discussed.

[1] V. K. Pecharsky and K. A. Gschneidner Phys. Rev. Lett. 78, 4494 (1997)

[2] E. Mendive-Tapia, J. Neugebauer, and T. Hickel, Phys. Rev. B 105, 064425 (2022)

[3] B. L. Gyorffy J. Phys. F.: Met. Phys. 15, 1337 (1985)

[4] A. Abadia-Huguet, E. Mendive-Tapia, et al., Appl. Mat. Today 44, 102749 (2025)

Bio: Dr. Eduardo Mendive studied Physics at the University of Barcelona and completed his PhD at the University of Warwick (UK), under the supervision of Prof. J. Staunton. His doctoral research focused on combining Density Functional Theory with statistical mechanics methods to enable ab initio thermodynamic modelling of magnetic materials. His thesis was recognized as outstanding PhD research by Springer and earned second place in the prestigious Sam Edwards Prize. Dr. Mendive has held postdoctoral positions at Forschungszentrum Jülich (Peter Grünberg Institute, directed by Prof. S. Blügel) and the Max Planck Institute for Iron Research in Düsseldorf (Department of Computational Materials Design, led by Prof. J. Neugebauer). He recently completed a Marie Curie Individual Fellowship and has been appointed lecturer in the Department of Condensed Matter Physics at the University of Barcelona. Dr. Mendive's research specializes in the first-principles computational study of magnetic materials, with a particular focus on their thermodynamic properties and the prediction of functional magnetic phase transitions. His work has direct relevance to a range of technological applications, including environmentally friendly solid-state caloric refrigeration. He enjoys close collaboration with experimental groups and aims to bridge theoretical models with real-world applications in magnetism and materials science. More recently, he has expanded his research to include polymeric materials, exploring their potential as elastocaloric refrigerants.