Abstrac t
In this presentation\, I will show two different approac hes to probe spin waves using a scanning NV microscope. The first is relax ometry\, which allows the detection of thermal spin waves through the magn etic noise they produce. This noise accelerates the relaxation of the NV c enter\, and is directly visible in the emitted photoluminescence\, reveali ng the position of domain walls in which low-frequency spin-wave modes are confined. I will also demonstrate how this qualitative method can be used to determine the handedness of magnetic textures and therefore the sign o f the underlying Dzyaloshinskii-Moriya interaction. In the second approach \, we excite spin waves with a coplanar wave guide. When they are resonant with the magnetic transition of the NV center\, the microwave stray field that they generate drives this transition. This mechanism can be probed d irectly with ODMR\, or more quantitatively with Rabi oscillations. This me thod allows\, for example\, the mapping of propagating spin waves. I will illustrate this technique with the exploration of nonlinear frequency-mult iplication phenomena in microstructured Py films. Finally\, I will also pr esent results about the imaging of complex magnetic textures\, and how we can analyze stray field maps to extract information about them. In particu lar\, I will focus on the stabilisation of magnetic vortices at room tempe rature in microstructures of the van der Waals magnet Fe5GeTe2.