Spin wave excitations in magnetic helices and skyrmion lattices

Chiral magnets are materials that lack inversion symmetry in their crystal structure \nand contain a number of different magnetic phases. In this thesis we focus \non cubic crystals. Besides a field-polarized phase for strong applied magnetic \nfields and a paramagnetic phase above a critical temperature, there are the more \ninteresting helical and conical phases as well as, most prominently, a trigonal \nlattice of topologically stable magnetic whirls, so-called skyrmions. Their recent \ndiscovery in MnSi has sparked a great interest in them, largely because of their \ntopological nature and the prospects of novel applications, for instance in future \nmagnetic storage devices. The last three mentioned phases are spin textures \ndue to the Dzyaloshinskii-Moriya spin-orbit interaction which is induced by the \naforementioned lack of inversion symmetry. We theoretically study spin wave \nexcitations with a focus on these phases, which are essential to understand for \ndynamic applications.