Quantum dynamics of skyrmions and vortices in antiferromagnets

Abstract

Skyrmions are magnetic textures, that behave like particles. They exist as excitations within two-dimensional magnetic insulators and are promising candidates for future data storage. There has been a strong rise in interest in skyrmions in recent years, which is encouraged by several experimental observations of skyrmions in various magnetic thin-films. In this thesis we study the quantum mechanical propagation of skyrmions in thin film antiferromagnets, using the finite temperature path integral formalism for spins. Using field theoretical tools like the Faddeev-Popov technique, we treat the coordinate of a skyrmion as a dynamical variable and derive an effective action for the skyrmion position. We find that the spin wave fluctuations around a skyrmion give rise to damping of the skyrmion's motion and also gives rise to effective mass contributions.