2025/05/25 by E. R. Cardozo de Oliveira, Claire M. Xiang, de Oliveira, E. R. Cardozo +15
Engineering · Physics and Astronomy · #Advanced Materials Characterization Techniques #FOS: Physical sciences #Magnetic properties of thin films #Materials Science (cond-mat.mtrl-sci) #Surface and Thin Film Phenomena
paper · pdf · doi:10.48550/arxiv.2505.19370
openalex publication_date 2025/05/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Superlattices presenting a spatial modulation of the elastic properties appear as a main tool to reach the THz regime in nanoacoustic devices. The exploration of alternative materials with multifunctional properties remains a fertile domain of research. In this work, we study the structural, magnetic, and acoustic characteristics of nanometric superlattices made of Pt/Co. The samples present a well defined periodicity, as determined by X-ray reflectometry, whereas scanning transmission electron microscopy with local compositional analysis reveals that the superlattices present a modulation in composition instead of sharp interfaces. The policrystalline nature of the superlattices is evidenced both by X ray diffraction and transmission electron microscopy. Magnetization measurements show a perpendicular magnetic anisotropy for the higher Co concentrations. Picosecond acoustic experiments evidence that the studied samples support short-lived acoustic modes up to 900 GHz, and up to 7 acoustic echoes at lower frequencies.These are promising results for the development of magnetoacoustic devices working at ultrahigh frequencies.