Spectrum evolution and chirping of laser-induced spin wave packets in thin iron films

Filatov, Ia. A.; Gerevenkov, P. I.; Wang, M.; Rushforth, A. W.; Kalashnikova, A. M.; Khokhlov, N. E.

Abstract

We present an experimental study of ultrafast optical excitation of magnetostatic surface spin wave (MSSW) packets and their spectral properties in thin films of pure iron. As the packets leave the excitation area and propagate in space, their spectra evolve non-trivially. Particularly, low or high frequency components are suppressed at the border of the excitation area depending on the orientation of the external magnetic field with respect to the magnetocrystalline anisotropy axes of the film. The effect is ascribed to the ultrafast local heating of the film. Furthermore, the time resolution of the implemented all-optical technique allows us to extract the chirp of the MSSW packet in the time domain via wavelet analysis. The chirp is a result of the group velocity dispersion of the MSSW and, thus, is controlled by the film's magnetic parameters, magnetization and anisotropy, and external field orientation. The demonstrated tunable modulation of MSSW wave packets with femtosecond laser pulses may find application in future magnonic-photonic hybrid devices for wave-based data processing.

Citation

Filatov, I. A., Gerevenkov, P. I., Wang, M., Rushforth, A. W., Kalashnikova, A. M., & Khokhlov, N. E. (2022). Spectrum evolution and chirping of laser-induced spin wave packets in thin iron films. Applied Physics Letters, 120(11), Article 112404. https://doi.org/10.1063/5.0077195

• Journal Article Type: Article
• Acceptance Date: Feb 25, 2022
• Online Publication Date: Mar 16, 2022
• Publication Date: Mar 14, 2022
• Deposit Date: Mar 18, 2022
• Publicly Available Date: Mar 18, 2022
• Journal: Applied Physics Letters
• Print ISSN: 0003-6951
• Electronic ISSN: 1077-3118
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 120
• Issue: 11
• Article Number: 112404
• DOI: https://doi.org/10.1063/5.0077195
• Keywords: Physics and Astronomy (miscellaneous)
• Public URL: https://nottingham-repository.worktribe.com/output/7610425
• Publisher URL: https://aip.scitation.org/doi/10.1063/5.0077195
• Additional Information: This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in (citation of published article) and may be found at https://aip.scitation.org/doi/10.1063/5.0077195