У оквиру семинара Центра за физику чврстог стања и нове материјале Института за физику у Београду, у понедељак, 20. октобра 2025. године у 12 часова у читаоници библиотеке „Др Драган Поповић“, др Срђан Ставрић (Институт за нуклеарне науке „Винча“) одржаће предавање:
Why all that fuss about altermagnets?
САЖЕТАК:
Altermagnets are an emerging class of magnetic materials characterized by a collinear compensated arrangement of magnetic moments and a momentum-dependent spin splitting in the band structure. This peculiar combination, arising from specific crystal symmetries [1], merges the most desirable traits of antiferromagnets – such as ultrafast dynamics without stray fields – with the strong time-reversal-symmetry-breaking responses characteristic for ferromagnets [2]. Found in a diverse range of materials from metals to insulators, altermagnets offer a versatile new platform for next-generation spintronics, paving the way for high-density magnetic memory and terahertz nano-oscillators [3]. This talk will explore the fundamental principles and significant potential of this exciting new class of materials. We will begin by establishing a new taxonomy of collinear magnets, introducing the distinct realms of ferromagnets, antiferromagnets, and altermagnets, and extending the concept to non-collinear p-wave magnets. A special focus will be on recent observation of p-wave magnetism in a spin-spiral type-II multiferroic NiI₂ [4]. We will explore how the symmetry-protected coupling between chirality and polar order enables electrical control of a primarily non-relativistic spin polarization in this material. Finally, we will examine the role of spin-orbit coupling in altermagnets and show what implications it may have on electronic and magnetic properties. In particular, we will focus on two-dimensional altermagnets, where this relativistic interaction cannot be neglected as it is the source of the magnetic anisotropy which is crucial for stabilizing long-range magnetic order at finite temperatures [5].
[1] L. Šmejkal, J. Sinova, T. Jungwirth: Phys. Rev. X 12, 031042 (2022)
[2] L. Šmejkal, J. Sinova, T. Jungwirth: Phys. Rev. X 12, 040501 (2022)
[3] C. Song, H. Bai, Z. Zhou et al.: Nat. Rev. Mater. 10, 473 (2025)
[4] Q. Song, S. Stavrić, P. Barone, A. Droghetti, D. S. Antonenko et al.: Nature 642, 64 (2025)
[5] M. Milivojević, M. Orozović, S. Picozzi, M. Gmitra, S. Stavrić: 2D Mater. 11, 035025 (2024)