Space-time duality in magnonics: Temporal diffraction in magnonic waveguides

In the present paper, we address the issue of the magnonic features due to the quadratic character of the dispersion of purely exchange SWs becoming more and more important due to a rapid progress in the technology of excitation of ultra-short SWs. Our interpretation in terms of time diffraction of the theoretical results and numerical simulations relies on the space/time duality principle that has already been successfully applied in ultrafast optics in the description of temporal evolution of short optical pulses. It was shown that time diffraction related effects lead to a considerable transformation of the signals transmitted through a magnonic channel in spintronic logic and computing devices that can be either detrimental or beneficial for the procedure of information processing. Specifically, time diffraction results in pulse expansion severely limiting the rate of information transfer. On the positive side, this feature can be effectively used to realize such important functionalities as pulse focusing/ compression and Fourier analysis which opens up novel promising opportunities in information processing.