The following seminar, presented by visiting academic Dr. Juba Bouaziz, will take place on Friday 18 September at 14:00 in MAS 2.05/6.
Speaker: Dr. Juba Bouaziz, University of Duisburg-Essen
Seminar Title: Magnetic Ordering in Weyl Semimetals and Kagome Magnets from First Principles
Abstract:
Understanding magnetic order in Weyl and kagome materials requires linking their electronic structure to the effective spin interactions that govern the resulting magnetic states. The talk begins with a brief introduction to the first-principles methodology used to construct such spin models, including benchmark applications to elemental magnets such as Fe and Co and the extraction of bilinear and biquadratic exchange interactions. The kagome Mn₃X (X= Ga, Ge and Sn) systems are then considered, where first-principles spin models combined with symmetry-based cluster multipoles are used to identify the low-energy 120° noncollinear magnetic structures. Bilinear and biquadratic exchange determine the low-energy manifold, while Dzyaloshinskii–Moriya interactions lift the remaining degeneracy and select the magnetic chirality. The approach is then applied to the RAlSi Weyl semimetals (R rare earth), where the incommensurate helical order is found to originate from competing short-range superexchange interactions rather than long-range RKKY exchange, while crystal-field-induced magnetic anisotropy controls the stability of the helical state relative to collinear order.
Biography:
Dr. Juba Bouaziz, https://www.linkedin.com/in/juba-bouaziz-3415093b8/ recently joined the University of Duisburg-Essen after winning a significant fellowship, (see https://www.uni-due.de/2025-12-08-zwei-top-talente-fuer-die-ude )
He describes his research at Duisburg “My methodology involves using classical computers as a platform for the discovery and design of quantum materials. To design and optimize materials for neuromorphic devices, such as spintronic synapses, I use a multiscale approach that combines quantum simulations and machine learning.”