We present the experimental observation of the localized amplification of externally excited spin waves in a transversely in-plane magnetized Ni81Fe19 magnonic waveguide by means of parallel pumping. By employing microfocussed Brillouin light scattering spectroscopy, we analyze the dependency of the amplification on the applied pumping power and on the delay between the input spin-wave packet and the pumping pulse. We show that there are two different operation regimes: At large pumping powers, the spin-wave packet needs to enter the amplifier before the pumping is switched on in order to be amplified while at low powers the spin-wave packet can arrive at any time during the pumping pulse.
@article{arxiv.1411.0830,
title = {A micro-sized parametric spin-wave amplifier},
author = {Thomas Brächer and Frank Heussner and Philipp Pirro and Tobias Fischer and Moritz Geilen and Björn Heinz and Bert Lägel and Alexander. A. Serga and Burkard Hillebrands},
journal= {arXiv preprint arXiv:1411.0830},
year = {2018}
}