Study of the magnetization reversal in individual nickel nanowires

The magnetization reversal of Ni nanowires was studied by anisotropic magnetoresistance measurements at temperatures between 15 and 300 K. The wires, synthesized by electrodeposition in a nanoporous polycarbonate membrane, are regular cylinders 22 mu m long with a diameter of 75 or 35 nm. The nucleation field was measured on individual nanowires as a function of the angle between the applied field and the wire axis. The results are quantitatively analyzed using classical magnetization reversal theories. Measurements of the nucleation field first obtained as a function of temperature evidence an extra uniaxial anisotropy induced by the contraction of the membrane at low temperature. Combining SQUID measurements and x-ray diffractometry at different temperatures, a clear picture of the large magnetoelastic effect was obtained. (C) 2000 American Institute of Physics. [S0021-8979(00)03902-5].

[1]  Amikam Aharoni,et al.  Angular dependence of nucleation by curling in a prolate spheroid , 1997 .

[2]  E. Ferain,et al.  Characterisation of nanoporous particle track etched membrane , 1997 .

[3]  P. Baltzer.  Effective Magnetic Anisotropy and Magnetostriction of Monocrystals , 1957 .

[4]  J. Ansermet.  REVIEW ARTICLE: Perpendicular transport of spin-polarized electrons through magnetic nanostructures , 1998 .

[5]  Meier,et al.  Nucleation of Magnetization Reversal in Individual Nanosized Nickel Wires. , 1996, Physical review letters.

[6]  J. Wegrowe,et al.  Anisotropic magnetoresistance as a probe of magnetization reversal in individual nono-sized nickel wires , 1998 .

[7]  M. Schabes,et al.  Micromagnetic theory of non-uniform magnetization processes in magnetic recording particles , 1991 .

[8]  C. Chien,et al.  Fabrication and Magnetic Properties of Arrays of Metallic Nanowires , 1993, Science.

[9]  K. Ounadjela,et al.  Magnetization processes in nickel and cobalt electrodeposited nanowires , 1997 .

[10]  Jean-Philippe Ansermet,et al.  Magnetic Properties of Nanosized Wires , 1996 .

[11]  S. E. Gilbert,et al.  Magnetoresistance of Ferromagnetic Nanowires , 1999 .

[12]  P. Galtier,et al.  In-plane periodic bicrystallinity in magnetic thin films , 1996 .

[13]  G. White,et al.  Electrical and thermal resistivity of the transition elements at low temperatures , 1959, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[14]  S. Schultz,et al.  Switching field studies of individual single domain Ni columns , 1997 .

[15]  Albert Fert,et al.  Giant magnetoresistance in magnetic multilayered nanowires , 1994 .

[16]  C. Graham,et al.  Introduction to Magnetic Materials , 1972 .

[17]  S. Schultz,et al.  Experimental study of individual ferromagnetic sub-micron cylinders , 1995 .

[18]  E. Wohlfarth,et al.  A mechanism of magnetic hysteresis in heterogeneous alloys , 1991 .

[19]  S. Shtrikman,et al.  Magnetization Curve of the Infinite Cylinder , 1958 .

[20]  J. Duvail,et al.  Observing magnetic nanowires by means of magnetic force microscopy , 1998 .

[21]  A. Aharoni.  Perfect and imperfect particles , 1986 .