Exploiting excitations of magnetic topological objects

Abstract

New physics emerge from the interplay between spin waves and magnetic topological objects. Excitation modes permit to exploit the full potential of topological objects and increase the range of applications, in particular in the field of insulator-based spintronics. Recently, the number of proposals leveraging excitation modes of topological objects is steadily increasing, such as in microwave generation and detection, spin-wave guides, parametrons and in neuromorphic spintronic devices. In this talk I will present three ways to exploit excitations of magnetic topological objects.First, I will show that domain walls in thin films behave as flexible strings with an extra internal degree of freedom1. A direct application is the use of domain walls as spin-wave guides and hosts of magnetic domain wall skyrmions. Moreover, by considering closed domain wall strings, I will derive analytically deformations, instabilities2,3, and excitation modes of skyrmions4.Second, I will propose the use of topological objects as tunable nanoscale in-materio frequency multipliers for spintronic systems5. I will show that the excitation of topological objects by fractions of the eigenfrequencies presents advantages compared to the well-known parametric excitation as it requires less energy input and does not generate instabilities away from the excited topological objects.Third, I will discuss a mechanism to controllably manipulate the direction and speed of domain walls in kagome antiferromagnets via a single linearly polarized spin-wave source6. In this case, the coupling of spin wave modes inside the non-collinear domain wall allows for a highly tunable spin-wave induced domain wall motion with a frequency dependent domain wall velocity.