title: Room-temperature ferromagnetism in carbon-doped ZnO.
abstract: We report ferromagnetism in carbon-doped ZnO. Our first-principles calculations based on density functional theory predicted a magnetic moment of 2.02 mu(B) per carbon when carbon substitutes oxygen in ZnO, and an ferromagnetic coupling among magnetic moments of the carbon dopants. The theoretical prediction was confirmed experimentally. C-doped ZnO films deposited by pulsed-laser deposition showed ferromagnetism with Curie temperatures higher than 400 K. The measured magnetic moment based on the content of carbide in the films [(1.5-3.0) mu(B) per carbon] was in agreement with the theoretical prediction. The magnetism is due to the Zn-C system in the ZnO environment.
authors.affiliation: Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542.
authors.forename: H
authors.initials: H
authors.lastname: Pan
authors.forename: J B
authors.initials: JB
authors.lastname: Yi
authors.forename: L
authors.initials: L
authors.lastname: Shen
authors.forename: R Q
authors.initials: RQ
authors.lastname: Wu
authors.forename: J H
authors.initials: JH
authors.lastname: Yang
authors.forename: J Y
authors.initials: JY
authors.lastname: Lin
authors.forename: Y P
authors.initials: YP
authors.lastname: Feng
authors.forename: J
authors.initials: J
authors.lastname: Ding
authors.forename: L H
authors.initials: LH
authors.lastname: Van
authors.forename: J H
authors.initials: JH
authors.lastname: Yin