title: Room temperature L1₀ phase transformation in binary CoPt nanostructures prepared by focused-electron-beam-induced deposition.
abstract: CoPt-C binary alloys have been fabricated by focused-electron-beam-induced deposition by the simultaneous use of Co₂(CO)₈ and (CH₃)₃CH₃C₅H₄Pt as precursor gases. The alloys are made of CoPt nanoparticles embedded in a carbonaceous matrix. TEM investigations show that as-grown samples are in an amorphous phase. By means of a room temperature low-energy electron irradiation treatment the CoPt nanoparticles transform into face-centered tetragonal L1₀ nanocrystallites. In parallel, the system undergoes a transition from a superparamagnetic to a ferromagnetic state at room temperature. By variation of the post-growth irradiation dose the electrical and magneto-transport properties of the alloy can be continuously tuned.
authors.affiliation: Physikalisches Institut, Goethe-Universität, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main, Germany. porrati@physik.uni.frankfurt.de
authors.forename: F
authors.initials: F
authors.lastname: Porrati
authors.forename: E
authors.initials: E
authors.lastname: Begun
authors.forename: M
authors.initials: M
authors.lastname: Winhold
authors.forename: Ch H
authors.initials: ChH
authors.lastname: Schwalb
authors.forename: R
authors.initials: R
authors.lastname: Sachser
authors.forename: A S
authors.initials: AS
authors.lastname: Frangakis
authors.forename: M
authors.initials: M
authors.lastname: Huth