title: Magnetoresistive phenomena in an Fe-filled carbon nanotube/elastomer composite.
abstract: DC magnetoresistive effects were observed in above-percolation-threshold loaded Fe-filled carbon nanotube/polyurethane-urea composite samples. A phenomenological model is derived from interpretation of resistance relaxation for a range of axial strains. The large instantaneous magnetoresistance of + 90% observed at low axial strain was a result of conduction pathway breaking caused by preferential orientation of the conducting nanotubes perpendicular to the axial current flow: a result of the magnetic torque experienced by the ferromagnetic nanotube core. At large strain the observed large instantaneous change in resistance of - 90% resulted from voltage-driven relaxation in the conducting nanotube network. At high axial strain the competition between voltage-driven relaxation and a magnetic torque gave rise to an oscillatory component of resistance relaxation.
authors.affiliation: Centre for Materials Research, Department of Physics, Queen Mary University of London, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Hudziak
authors.forename: A
authors.initials: A
authors.lastname: Darfeuille
authors.forename: R
authors.initials: R
authors.lastname: Zhang
authors.forename: T
authors.initials: T
authors.lastname: Peijs
authors.forename: G
authors.initials: G
authors.lastname: Mountjoy
authors.forename: G
authors.initials: G
authors.lastname: Bertoni
authors.forename: M
authors.initials: M
authors.lastname: Baxendale