著者
Kita Eiji Tsukuhara Naoki Sato Hidenori Ota Keishin Yangaihara Hideto Tanimoto Hisanori Ikeda Naoshi
出版者
American Institute of Physics
雑誌
Applied physics letters (ISSN:00036951)
巻号頁・発行日
vol.88, pp.152501, 2006-04
被引用文献数
22 19

We prepared high-purity oxygen-free and single-phase Ni nanocrystals using the gas condensation and deposition method in order to examine the random anisotropy model (RAM). The grain size of an as-prepared sample was estimated to be 8–10 nm. Thermal annealing increased grain sizes (D) up to 22 nm. Clear D6 dependence of the coercive force on a grain size smaller than 13 nm was obtained for samples prepared on both plastic and KBr single-crystal substrates. For larger grain sizes, Hc decreased with D–1 and these results clearly conform to the RAM in single-element nanocrystal systems. A local anisotropy constant was estimated from the slope of the D6 relation and the peak of Hc at D=13 nm.