Experimental determination and micromagnetic analysis of spin-wave modes in cylindrical nanowires

We report an experimental study of spin-wave modes in individual cylindrical nanowires, a textbook situation of confined spin waves in three-dimensional nanomagnetism. We observe discrete modes of thermal spin waves with microfocused Brillouin light scattering, whose frequencies 𝑓 shift to higher values as the applied longitudinal induction magnetic field 𝐵$_𝑧$ increases. Micromagnetic simulations allowed us to associate every 𝑓 ⁡(𝐵$_𝑧$) curve to a given spatial mode, labeled with radial and azimuthal indices ℓ and 𝑚.