著者
Peng D. L. Sumiyama Kenji Yamamuro S. Hihara Takehiko Konno T. J. ヒハラ タケヒコ スミヤマ ケンジ 隅山 兼治 日原 岳彦 Sumiyama K. Hihara T.
出版者
American Institute of Physics
雑誌
APPLIED PHYSICS LETTERS (ISSN:00036951)
巻号頁・発行日
vol.74, no.1, pp.76-78, 1999-01-04
被引用文献数
33

We have studied electrical conductivity, σ, and magnetoresistance in a CoO-coated monodispersive Co cluster assembly fabricated by a plasma-gas-aggregation-type cluster beam deposition technique. The temperature dependence of σ is described in the form of log σ vs 1/T for 7<T<80 K. The magnetoresistance ratio (ρ0-ρ3T)/ρ0 increases sharply with decreasing temperature below 25 K: from 3.5% at 25 K to 20.5% at 4.2 K. This marked increase (by a factor of 6) is much larger than those observed for conventional metal-insulator granular systems. These results are ascribed to the Coulomb blockade effect in the monodispersed cluster assemblies.