20.500.12556/RUL-185679 Laser-generated gigahertz surface acoustic waves with tunable amplitude during the magnetostructural phase transition in Fe-Rh thin films Laser-generated surface acoustic waves (SAWs) facilitate efficient information processing in modern spintronics and magnonics. The ability to tune the SAW parameters such as the amplitude is crucial to achieve acoustic control over magnonic properties. Such tunability can be achieved in phase-changing magnetic materials that accommodate both spin waves and SAWs. A promising material is the Fe-Rh alloy, a metallic antiferromagnet at room temperature that undergoes a phase transition to the ferromagnetic state accompanied by a crystal lattice expansion at 370 K. This transition can also be induced by femtosecond laser pulses. In this paper, we use the phase transition in a 60-nm Fe▫$_{49}$▫Rh▫$_{51}$▫ film to optically generate pulses of Gigahertz quasi-Rayleigh SAWs. We detect them via the photoelastic effect and show that the lattice transformation during the phase transition is a dominant strain-generation mechanism for above-threshold excitation. The weight of this contribution rises as the sample is heated closer to the antiferromagnetic-ferromagnetic transition temperature and “switches off” when heated above it, allowing for control of the SAW amplitude. A model based on thermodynamic parameters of Fe▫$_{49}$▫Rh▫$_{51}$▫ shows that the lattice transformation occurring within 95 ps effectively contributes to SAW generation happening on a comparable timescale, while nonequilibrium fast kinetics of the phase transition does not. Fe-Rh thin films magnetostructural phase transition surface acoustic waves spintronics magnonics Fe-Rh tanke plasti magnetostrukturni fazni prehodi površinski akustični valovi spintronika magnonika true false true Angleški jezik Slovenski jezik Članek v reviji 2026-08-17 14:50:19 2026-08-17 14:50:24 2026-08-18 04:04:48 0000-00-00 00:00:00 2026 0 0 12 str. Vol. 25, art. 054062 2026 0000-00-00 PostprintKoncna Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 537.622:621.318.1 2331-7019 10.1103/fgq4-ff7g 287779075 Gimaev_..._Laser-generated....pdf Gimaev_..._Laser-generated....pdf 1 D03A3E7E35C25C982DC8F332AAE4EBDC a597ea1115127e13b92c107d944c02d9c95dc5b04e3d0dde5f3a0c66834b869b 0a9a5ff7-9a3a-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=244453 https://journals.aps.org/prapplied/abstract/10.1103/fgq4-ff7g 1 d675b283-9a39-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=244452 Fakulteta za strojništvo 0 0 0