Enhanced Transmission through Squeezed Modes in a Self-Cladding Magnonic Waveguide

We study spin-wave propagation in 360-nm wide Ni80Fe20 nanowires using all-electrical spin-wave spectroscopy. Creating a zigzag-like magnetization state, we find enhanced spin-wave transmission compared to the states of more homogeneous magnetization. Micromagnetic simulations show that the spin waves propagate in narrow channels, which in particular, are remotely positioned from the edges. The internal channels reflect field-controlled self-cladding. Interestingly, rotation of the magnetic field at a specific value is found to vary the propagation velocity without changing the eigenfrequency. This opens the perspective of the velocity modulation transistor following a concept known from semiconductor electronics.