In-plane topological spin textures in chiral magnets

This thesis proposes and theoretically investigates novel in-plane magnetized topological spin textures, exploring their static and dynamical properties in both ferromagnets and antiferromagnets using analytical and numerical methods. Chapter 1 reviews the fundamentals of chiral magnetism, magnetically ordered phases, and the classification of topological spin textures, providing the foundation for the models and analyses that follow. In Chapter 2, we focus on exploring the fundamental static and dynamical properties of a novel topological spin texture - asymmetric antibimeron (AAB). To this end, we first propose a theoretical model for its stabilization. As for its static properties, we analyze AAB's shape and stability, and demonstrate that it can possess two topologically distinct states of opposite topological charge but of the same energy. As for its dynamical properties, we show that its stability can be controlled by the direction of applied current, and by extending Thiele’s equation approach to asymmetric spin textures, we analytically capture new dynamics phenomena. Finally, we propose an efficient scheme to change the net topological charge of the system via controlled collisions between AABs. In Chapter 3, we shift our attention to the dynamical excitations of AABs. Accordingly, we study the spin eigenmodes of individual AABs and their clusters. Focusing first on an isolated AAB, we show that its spectrum comprises three localized eigenmodes. We then examine clusters of N AABs, in which inter-AAB coupling produces an N-fold splitting of the absorption spectrum. We explain the obtained numerical results by introducing a spring-mass model of coupled meron pairs. In Chapter 4, we aim to propose an effective approach for creating spin textures. To do so, we explore an optical method that uses the orbital angular momentum of light to generate both isolated AABs and AAB clusters. Chapters 2 through 4 focus exclusively on ferromagnetic systems. In Chapter 5, we extend our study to antiferromagnetic materials. We demonstrate AAB stabilization and explore their magnon-driven dynamics, revealing how nonreciprocal antiferromagnetic magnons couple to and propel AAB motion. While this thesis centers on the study of AABs, we draw on both established and more exotic spin textures for comparison where relevant. Finally, in Chapter 6, we present our conclusions.