Anomalous frequency scaling of acoustic phonon damping in freestanding nickel cavities fabricated via laser delamination
Year: 2025
Type: article
Abstract: Single-shot picosecond (ps) laser-induced delamination allows for the direct generation of suspended membranes from a continuous metallic film, offering a promising platform for the control of ultrafast magnetization dynamics driven by acoustic waves. Using the picosecond-ultrasonics method, we demonstrate that long-lived low-frequency acoustic waves can be optically excited in the delaminated cavities. At the same time, higher-frequency modes above 60 GHz exhibit a surprisingly fast damping, following a scaling law incompatible with the expected attenuation mediated by phonon–phonon scattering. Comparing measurements between delaminated cavities and a benchmark nickel film in contact with the substrate, we link our findings to structural modifications of the nickel crystal induced by the delamination process.
Source: Applied Physics Letters
DOI: 10.1063/5.0263631
Institutions: University of Luxembourg, Fritz Haber Institute of the Max Planck Society, Consorzio Nazionale Interuniversitario per le Telecomunicazioni, National Institute of Optics, University of Brescia, CIC nanoGUNE, Centre National de la Recherche Scientifique, École Polytechnique, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Institut Polytechnique de Paris, Université Paris Diderot, Laboratoire des Solides Irradiés, Ikerbasque, Umeå University
Language: English
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Awards: G1575104644, G2082387890, G2409173359, G3385414978, G4731917642, G5683704876, G5728265019, Ultrafast nonthermal spin dynamics in magnetoplasmonic nanomaterials, Ultrafast Raman Technologies for Protein Identification and Sequencing, G7176779267, G8347752858, G842821097, G8757771404, G8983811662
OpenAlex ID: W4413284286