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Anton Hromov, Andrej Zorko and Matej Pregelj together with colleagues from the Department for Thin Films and Surfaces F3 and colleagues from Serbia published the article: Perpendicular magnetic anisotropy in multilayers arising from the interplay of thermal strains and diffusion-driven plastic deformation, in the journal Acta Materialia (https://doi.org/10.1016/j.actamat.2024.120320). Magnetic films with perpendicular magnetic anisotropy (PMA) are the basis for efficient data storage and future spintronic devices. PMA originates mainly from surface effects at the interface between two layers and decreases rapidly with increasing layer thickness. Consequently, the individual layers in such films, with a large number of alternating magnetic and non-magnetic layers, are typically less than a nanometer thin. Using ferromagnetic resonance measurements, the group showed that strong PMA can also be achieved in multilayer Si/Ni films with a thickness of individual layers more than 10 nm. The key mechanisms are thermally imposed stress, plastic deformation, and diffusion, which impose PMA via magnetoelastic coupling. Such a process paves the way for the production of PMA films, which avoids the complex and expensive production of atomically thin multilayer films.

Prof. dr. Miha Ravnik from Faculty of Mathematics and Physics University of Ljubljana and J. Stefan Institute is the recipient of the prominent Samsung Prize for Mid Career Achievement awarded by the International Liquid Crystal Society, for his contributions to the physics and simulations of liquid crystals. He received the prize at the recent 29th International Liquid Crystal Conference in Rio de Janeiro. The Prize is awarded biannually to two best mid-career scientists for their demonstrated scientific excellence in the general field of liquid crystal science. 

George Cordoyiannis and colleagues from KU Leuven (Belgium), University of Colorado (USA), University of Hull (UK) have published an article in Physical Review E reporting the existence of a new intermediate Nx phase in one of the two first discovered ferroelectric nematic liquid crystals, namely, RM734. The temperature range of this phase is 1.15 ± 0.10 K and the N-Nx transition enthaply is minute (<  5 mJ/g).

https://doi.org/10.1103/PhysRevE.110.014703

Remarkable advances in the understanding of topological constraints in biological and soft matter physics in the past few years stimulated the European COST collaboration EUTOPIA to write a comprehensive review paper on topological effects in systems ranging from DNA and genome organization to entangled proteins, polymeric materials, liquid crystals, and theoretical physics, with the main intention of reducing the barriers between different subfields of soft and biological matter.  Simon Čopar, Miha Ravnik, Primož Ziherl, and Slobodan Žumer, colleagues from the “Jožef Stefan” Institute and the Faculty of Mathematics and Physics of the University of Ljubljana, together with colleagues from the EUTOPIA group, published a review article “Topology in soft and biological matter” in the journal Physics Reports.

Physics Reports 1075, 18 July 2024, Pages 1-137, Topology in soft and biological matter.

https://doi.org/10.1016/j.physrep.2024.04.002

COBISS.SI-ID 32291367 IF = 29.9

PEKLAR, Rok, MIKAC, Urška, SERŠA, Igor. The effect of battery configuration on dendritic growth : A magnetic resonance microscopy study on symmetric lithium cells. Batteries. 2024, vol. 10, art. 165, 13 str. ISSN 2313-0105. https://www.mdpi.com/2313-0105/10/5/165.

The potential of metallic lithium to become the anode material for next-generation batteries is hampered by significant challenges, chief among which is dendrite growth during battery charging. These dendrite structures not only impair battery performance but also pose safety risks. In this study, a recently introduced indirect imaging approach which is based on 1H MRI of the electrolyte was used to sequentially image dendrite growth in different configurations of symmetric lithium cells. The measured sequential images allowed for the measurement of dendrite growth in each cell using volumetric analysis. The growth results confirmed our theoretical prediction that the growth across cells is uneven in a parallel circuit, and even in a series circuit.