Anomalous frequency scaling of acoustic phonon damping in freestanding nickel cavities fabricated via laser delamination

Year: 2025

Authors: Rodrnguez A.V., Rossetti A., Gandolfi M., Elgueta Y.U., Modin E.B., Starikovskaia S., Chng T.L., Temnov V.V., Vincenti M.A., Brida D., Vavassori P., Maccaferri N.

Autors Affiliation: Univ Luxembourg, Dept Phys & Mat Sci, 162A Ave Faiencerie, L-1511 Luxembourg, Luxembourg; Fritz Haber Inst, Dept Phys Chem, Max Planck Soc, D-14195 Berlin, Germany; Univ Brescia, Dipartimento Ingn Informaz, Via Branze 38, I-25123 Brescia, Italy; CNR, Ist Nazl Ott, Via Branze 45, I-25123 Brescia, Italy; Consorzio Nazl Interuniv Telecomunicazioni CNIT, Viale GP Usberti 181-A Sede Scientif Ingn Palazzin, I-43124 Parma, Italy; CIC NanoGUNE, Tolosa Hiribidea 76, Donostia San Sebastian 20018, Spain; Inst Polytech Paris, CNRS, CEA DRF IRAMIS, Ecole Polytech,LSI, F-91128 Palaiseau, France; IKERBASQUE Basque Fdn Sci, Plaza Euskadi 5, Bilbao 48009, Spain; Umea Univ, Dept Phys, Linnaeus Vag 24, S-90187 Umea, Sweden.

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. (c) 2025 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

Journal/Review: APPLIED PHYSICS LETTERS

Volume: 127 (7)      Pages from: 72201-1  to: 72201-8

More Information: N.M. acknowledges support from the Swedish Research Council (Grant No. 2021-05784), the Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows Programme (Grant No. 2023.0089), the European Research Council (ERC Starting Grant No. 101116253 MagneticTWIST), and Wenner-Gren Stiftelserna (Grant No. UPD2022-0074). A.V.R., D.B., and N.M. acknowledge support from the European Commission (Grant No. 964363) and the Luxembourg National Research Fund (Grant No. C19/MS/13624497). D.B. acknowledges support from the European Regional Development Fund (Project UltrafastLux 2 Grant No. 2023-01-04). Y.U.E. and P.V. acknowledge support from the Spanish Ministry of Science and Innovation under the Maria de Maeztu Units of Excellence Program (Grant No. CEX2020-001038-M) and Project No. PID2021-123943NB-I00 (OPTOMETAMAG), as well as Predoctoral Fellowship No. PRE2022-103017 and the Research Program for International Talents at Ecole Polytechnique. M.A.V. and M.G. acknowledge financial support from the MUR CARAMEL project (No. CUP D73C24000220001).
KeyWords: Acoustic waves; Dynamic frequency scaling; Fabrication; Metallic films; Nickel; Phonons
DOI: 10.1063/5.0263631