title: Probing one antiferromagnetic antiphase boundary and single magnetite domain using nanogap contacts.
abstract: We have probed one antiferromagnetic (AF) antiphase boundary (APB) and a single Fe(3)O(4) domain using nanogap contacts. Our experiments directly demonstrate that, in the case of probing one AF-APB, a large magnetoresistance (MR), high resistivity, and a high saturation field are observed as compared with the case of probing a single Fe(3)O(4) domain. The shape of the temperature-dependent MR curves is also found to differ between the single domain and one of the AF-APB measurements, with a characteristic strong temperature dependence for the single domain and temperature independence for the one AF-APB case. We argue that these observations are indicative of profound changes in the electronic transport across APBs. The investigated APB defects increase the activation energy and disturb the long-range charge ordering of monodomain Fe(3)O(4).
authors.affiliation: CRANN, School of Physics, Trinity College Dublin, Dublin 2, Ireland. wuhc@tcd.ie
authors.forename: Han-Chun
authors.initials: HC
authors.lastname: Wu
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abid
authors.forename: Byong S
authors.initials: BS
authors.lastname: Chun
authors.forename: Rafael
authors.initials: R
authors.lastname: Ramos
authors.forename: Oleg N
authors.initials: ON
authors.lastname: Mryasov
authors.forename: Igor V
authors.initials: IV
authors.lastname: Shvets
mesh_terms: D005290:Ferric Compounds / Q000737:chemistry*; D008280:Magnetics; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size
chemical_list: D005290:Ferric Compounds