Small-angle polarized neutron scattering study of spherical FeN nano-particles for magnetic recording tape

Oku, Takayuki   ; Kikuchi, Takayuki*; Shinohara, Takenao   ; Suzuki, Junichi; Ishii, Yuya*; Takeda, Masayasu  ; Kakurai, Kazuhisa; Sasaki, Yuji*; Kishimoto, Mikio*; Yokoyama, Makoto*; Nishihara, Yoshikazu*

The microscopic determination of the magnetic moment in the FeN nano-particles by means of polarized neutron diffraction experiment is reported. These particles had been developed by industrial researchers for use in high-density magnetic tape, and the particles were coated with proprietary nonmagnetic material. Polarized neutrons were used to measure the magnetic-nuclear interference contributions and, given the known crystal structure, the detailed analysis allowed to determine the magnetic moments on the different Fe-sites. The future perspectives of this technique using the high-intensity powder instrument in combination with pulsed magnetic high-field at J-PARC including the possible industrial application is discussed.