Effect of Exchange Interactions on the Coercivity of SmCo5 Nanoparticles Made by Cluster Beam Deposition

Authors

O Akdogan, University of Delaware Newark
W Li, University of Delaware Newark
B Balasubrmanian, University of Nebraska Lincoln
David J. Sellmyer, University of Nebraska-LincolnFollow
George C. Hadjipanayis, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2013

Citation

Advanced Functional Materials 23 (2013)

Abstract

Single crystal SmCo₅ nanoparticles with an average size of 3.5 nm are produced by cluster-beam deposition. When deposited without matrix, the nanoparticles showed a super-paramagnetic be-havior with a blocking temperature of 145 K. Dispersion of the SmCo₅ nanoparticles in a carbon matrix results in an increase in both the coercivity and the blocking temperature. Room temperature coercivities as high as 12 kOe are obtained for the first time in mono-layers of SmCo₅ nanoparticles dispersed in C matrix. δM plots show that the interactions in the samples are of exchange type, which can decrease the overall effective anisotropy and coercivity according to the random-anisotropy model. Coercivity is found to be inversely proportional to the packing density of the particles. SmCo₅ nanoparticles with high coercivity are potential candidates for the next generation ultra-high-density magnetic recording media.