TITLE

Inversed tunneling magnetoresistance in hybrid FePt/Fe3O4 core/shell nanoparticles systems

AUTHOR(S)
Yunpeng Zhang; Hui Xing; Poudyal, Narayan; Nandwana, Vikas; Chuan-bing Rong; Shi-shen Yan; Hao Zeng; Liu, J. P.
PUB. DATE
November 2010
SOURCE
Journal of Applied Physics;Nov2010, Vol. 108 Issue 10, p103905
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Magnetotransport studies were performed on hybrid FePt/Fe3O4 core/shell nanoparticle systems. The linear relationship of LnR versus T-1/2 with and without a magnetic field confirms the physical picture of thermally assisted interparticle tunneling. A sign inversion of tunneling magnetoresistance (TMR) from negative to positive with decreasing temperature was observed. In the high temperature region, the core/shell nanoparticles show negative TMR similar to that of Fe3O4 nanoparticles. The magnitude of the TMR in the FePt/Fe3O4 core/shell nanoparticle systems is smaller than that in Fe3O4 nanoparticle systems, likely due to lower spin polarization of conducting electrons in FePt. However the MR becomes positive in the low temperature region. We propose that this behavior originates from the resonance tunneling between the FePt cores via the defect states near the Fermi level in the Fe3O4 shells which dominates the magnetotransport of the FePt/Fe3O4 nanoparticle system at low temperatures.
ACCESSION #
55509680

 

Related Articles

  • Finite-element simulations of hysteretic ac losses in a bilayer superconductor/ferromagnet heterostructure subject to an oscillating transverse magnetic field. Genenko, Y. A.; Rauh, H.; Krüger, P. // Applied Physics Letters;4/11/2011, Vol. 98 Issue 15, p152508 

    Numerical simulations of hysteretic ac losses in a bilayer superconductor/ferromagnet heterostructure subject to an oscillating transverse magnetic field are performed within the quasistatic approach, calling upon the ANSYS finite-element software program and exploiting...

  • Tunable exchange bias effect in magnetic Bi0.9Gd0.1Fe0.9Ti0.1O3 nanoparticles at temperatures up to 250K. Basith, M. A.; Khan, F. A.; Ahmmad, Bashir; Kubota, Shigeru; Hirose, Fumihiko; Ngo, D.-T.; Tran, Q.-H.; Mølhave, K. // Journal of Applied Physics;2015, Vol. 118 Issue 2, p023901-1 

    The exchange bias (EB) effect has been observed in magnetic Bi0.9Gd0.1Fe0.9Ti0.1O3 nanoparticles. The influence of magnetic field cooling on the exchange bias effect has also been investigated. The magnitude of the exchange bias field (HEB) increases with the cooling magnetic field, showing that...

  • Abnormal magnetic behaviors and large magnetocaloric effect in MnPS3 nanoparticles. Zeng, R.; Wang, S. Q.; Du, G. D.; Wang, J. L.; Debnath, J. C.; Shamba, P.; Fang, Z. Y.; Dou, S. X. // Journal of Applied Physics;Apr2012, Vol. 111 Issue 7, p07E144 

    A nanostructured honeycomb lattice consisting of MnPS3 nanoparticles synthesized via the ion-exchange technique was found to have restacked molecular layers stabilized by H2O insertion between the layers. Susceptibility (χ) and heat capacity measurements showed the absence of long range...

  • Controllable switching of vortex chirality in magnetic nanodisks by a field pulse. Gaididei, Yuri; Sheka, Denis D.; Mertens, Franz G. // Applied Physics Letters;1/7/2008, Vol. 92 Issue 1, p012503 

    We propose a way of fast switching the chirality in a magnetic nanodisk by applying a field pulse. To break the symmetry with respect to clockwise or counterclockwise chirality, a mask is added by which an inhomogeneous field influences the vortex state of a nanodisk. Using numerical...

  • The Effect Of Temperature On Magnetic Behavior Of Magnetite Nanoparticles And Its Nanocomposites. Kong, I.; Ahmad, S. H.; Abdullah, M. H.; Yusoff, A. N. // AIP Conference Proceedings;6/1/2009, Vol. 1136 Issue 1, p830 

    The magnetic properties of magnetite nanoparticles and magnetite-thermoplastic natural rubber (TPNR) nanocomposites was prepared by melt-blending method has been studied using vibrating sample magnetometer (VSM). The saturation magnetization (MS), remanence (MR), squareness (MR/MS), coercivity...

  • Electromagnetic characteristics of surface modified iron nanowires at x-band frequencies. Liang, W. F.; Yang, R. B.; Lin, W. S.; Jian, Z. J.; Tsay, C. Y.; Wu, S. H.; Lin, H. M.; Choi, S. T.; Lin, C. K. // Journal of Applied Physics;Apr2012, Vol. 111 Issue 7, p07B545 

    Surface modified iron nanowire nanoparticles were prepared via reduction of iron salts (FeCl3· 6H2O) under an applied magnetic field. To minimize the surface oxidation, dextran (0.05 and 0.25 wt. %) was added during the process and formed a thin passive layer over iron nanowires with alcohol...

  • The Influence of YBaCuNbO Nanoparticle Addition on the Superconducting Properties of Single Domain YBCO Bulks. Li, J.; Yang, W.; Wang, M.; Yang, P.; Ma, J. // Journal of Superconductivity & Novel Magnetism;Nov2014, Vol. 27 Issue 11, p2487 

    Single-domain YBCO superconductors with different additions of nanometer Y Ba CuNbO (YNb2411), based on the solid phase of [(100- x)Y BaCuO (Y211) + x YNb2411] ( x = 3, 5, 7, 10, 12) and liquid phase of (Y211 + 9BaCuO + 6CuO), were successfully fabricated by a modified top seeded infiltration...

  • Size effect of strong-coupled superconducting In2Bi nanoparticles: An investigation of short-range electron phonon coupling. Po-Yu Lin; Gandhi, Ashish Chhaganlal; Sheng Yun Wu // Journal of Applied Physics;2015, Vol. 117 Issue 17, p17E316-1 

    We report the influence of the nanosized effect on the superconducting properties of bimetallic In2Bi nanoparticles. In this study, the temperature- and applied magnetic field-dependence of the magnetization were utilized to investigate the electron-phonon coupling effect while controlling...

  • Magnetic-field-dependent optical transmission of nickel nanorod colloidal dispersions. Klein, Tobias; Laptev, Aleksej; Günther, Annegret; Bender, Philipp; Tschöpe, A.; Birringer, R. // Journal of Applied Physics;Dec2009, Vol. 106 Issue 11, p114301 

    Aqueous dispersions of nickel nanorods, ≈13 nm in diameter and 40–160 nm in length, were synthesized using ac electrodeposition into porous alumina templates. The nanorods in suspension can be aligned by modest magnetic fields, which leads to a change in the optical transmittance of...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics