title: Magnetic properties of single-crystalline CoSi nanowires.
abstract: We have observed unusual ferromagnetic properties in single-crystalline CoSi nanowire ensemble, in marked contrast to the diamagnetic CoSi in bulk. High-density freestanding CoSi nanowires with B20 crystal structure are synthesized by a vapor-transport-based method. The reaction of cobalt chloride precursor with a Si substrate produces high-aspect-ratio CoSi nanowires. The high-resolution transmission electron microscopy and electron diffraction studies reveal superlattice structure in CoSi nanowires with twice the lattice parameter of simple cubic CoSi lattice. The zero-field-cooled and field-cooled (ZFC-FC) measurements from the nanowire ensemble show freezing of the disordered surface spins at low temperatures. The magnetoresistance (MR) measurements of single nanowire devices show a negative MR whose magnitude gets larger at lower temperatures.
authors: Department of Chemistry, KAIST, Daejeon 305-701, Korea.
authors: Kwanyong
authors: K
authors: Seo
authors: K S K
authors: KS
authors: Varadwaj
authors: Paritosh
authors: P
authors: Mohanty
authors: Sunghun
authors: S
authors: Lee
authors: Younghun
authors: Y
authors: Jo
authors: Myung-Hwa
authors: MH
authors: Jung
authors: Jinhee
authors: J
authors: Kim
authors: Bongsoo
authors: B
authors: Kim