Unusually high coercivity at room temperature in CoFe/sub 2/O/sub 4/ nanoparticles

Author

Chinnasamy, C.N. ; Jeyadevan, B. ; Perales-Perez, O. ; Tohji, K. ; Shinoda, K. ; Kasuya, A.

Author_Institution

Center for Interdisciplinary Res., Tohoku Univ., Sendai, Japan

fYear

2002

Abstract

Summary form only given. Preparing high coercivity CoFe/sub 2/O/sub 4/ nanoparticles suitable for high-density recording is still a challenge. The theoretical values for a random system of spherical, non-interacting single-domain CoFe/sub 2/O/sub 4/ particles with cubic anisotropy have been predicted to be: M/sub s/ (300 K)=80.8 emu/gm, H/sub c/(300 K)=5.3 kOe and M/sub r//M/sub s/=0.83. Here, for the first time, we report the synthesis of CoFe/sub 2/O/sub 4/ nanoparticles of about 40 nm with unusual high coercivity of 4.3 kOe at room temperature (RT).

Keywords

cobalt compounds; coercive force; ferrites; magnetic particles; materials preparation; nanoparticles; particle size; 300 K; 40 nm; CoFe/sub 2/O/sub 4/; CoFe/sub 2/O/sub 4/ nanoparticles; cubic anisotropy; high coercivity; high-density recording; room temperature; spherical noninteracting single-domain particles; Anisotropic magnetoresistance; Coercive force; Grain size; Magnetic anisotropy; Magnetic properties; Nanoparticles; Reluctance motors; Temperature; Torque; X-ray scattering;

fLanguage

English

Publisher

ieee

Conference_Titel

Magnetics Conference, 2002. INTERMAG Europe 2002. Digest of Technical Papers. 2002 IEEE International

Conference_Location

Amsterdam, The Netherlands

Print_ISBN

0-7803-7365-0

Type

conf

DOI

10.1109/INTMAG.2002.1001492

Filename

1001492