Abstract
Metamaterials, designed to exhibit properties beyond those found in nature, enable unprecedented control over physical phenomena through flexible band structure engineering. This work introduces a hybrid magnonic-plasmonic metamaterial that allows spatiotemporal manipulation of spin-wave transport at micrometer scales and sub-microsecond timescales. The system integrates a plasmonic metamaterial, comprising Au nanodisk arrays arranged in a 1D periodic stripe pattern, with a low-damping yttrium iron garnet (YIG) film as the spin-wave transport medium. Short laser pulses (100-500 ns) excite surface lattice resonances (SLRs) in the plasmonic stripes, inducing thermoplasmonic heating and generating a striped temperature profile. This dynamic thermal modulation periodically alters the YIG film's saturation magnetization, forming a laser-controlled magnonic crystal. Time-resolved propagating spin-wave spectroscopy reveals tunable bandgaps and minibands arising from Bragg reflection. By adjusting the plasmonic stripe pattern, laser pulse duration, or power, this system enables precise control over spin-wave transport, paving the way for reconfigurable wave-based computing devices.