Growth and magnetic characterization of Co nanoparticles obtained by femtosecond pulsed laser deposition

Cebollada, A.; García Martín, J. M.; Clavero, C.; Balcells, Ll.; Estradé, S.; Arbiol, J.; Peiró, F.; Smith, C.; Clarke, R.; Martínez, L.; Huttel, Y.; Román, E.; Telling, N. D.; van der Laan, G.

Abstract

We present a detailed study on the morphology and magnetic properties of Co nanostructures deposited onto oxidized Si substrates by femtosecond pulsed laser deposition. Generally, Co disks of nanometric dimensions are obtained just above the ablation threshold, with a size distribution characterized by an increasingly larger number of disks as their size diminishes, and with a maximum disk size that depends on the laser power density. In Au/Co/Au structures, in-plane magnetic anisotropy is observed in all cases, with no indication of superparamagnetism regardless of the amount of material or the laser power density. Magnetic force microscopy observations show coexistence of single-domain and vortex states for the magnetic domain structure of the disks. Superconducting quantum interference device magnetometry and x-ray magnetic circular dichroism measurements point to saturation magnetization values lower than the bulk, probably due to partial oxidation of the Co resulting from incomplete coverage by the Au capping layer.

Citation

Cebollada, A., García Martín, J. M., Clavero, C., Balcells, L., Estradé, S., Arbiol, J., Peiró, F., Smith, C., Clarke, R., Martínez, L., Huttel, Y., Román, E., Telling, N. D., & van der Laan, G. Growth and magnetic characterization of Co nanoparticles obtained by femtosecond pulsed laser deposition. Physical review B: Condensed matter and materials physics, 79(1), https://doi.org/10.1103/physrevb.79.014414

• Journal Article Type: Article
• Online Publication Date: Jan 12, 2009
• Deposit Date: May 22, 2024
• Journal: Physical Review B
• Print ISSN: 1098-0121
• Electronic ISSN: 1550-235X
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 79
• Issue: 1
• DOI: https://doi.org/10.1103/physrevb.79.014414
• Public URL: https://keele-repository.worktribe.com/output/831104
• Publisher URL: https://journals.aps.org/prb/abstract/10.1103/PhysRevB.79.014414