Pulsed spin wave propagation in a magnonic crystal

Abstract

Amplitude, frequency, and time domain characteristics have been mapped for short spin wave pulses inside a magnonic crystal. A space- and time-resolved magnetoinductive probing system has been used to detail the spin wave spectral, propagation, and evolution characteristics in a geometrically structured yttrium iron garnet film. Experiments have been performed using magnetostatic surface spin waves excited in a chemically-etched magnonic crystal, ultrafast pulsed excitation of the spin waves, and direct spin wave detection using a scannable magnetoinductive probe connected to a synchronized fast oscilloscope. The results show how the frequency discriminating effect of a magnonic bandgap decreases as the excitation pulse width decreases. They also show how the use of rectangular pulses compromise the magnonic crystal performance because of the high frequency components of such pulses. Space and time maps show how these components are transmitted without additional damping.