Structural and magnetic properties of Ni nanowires grown in mesoporous silicon templates

Properties of Ni and Ni–Fe nanowires electrochemically deposited into a porous alumina template

“…The decrease of specific magnetization after heating in vacuum (measuring specificity) could be caused by interaction of the metal with the matrix material of the pores and the formation of a non-ferromagnetic alloy. Similar effect was observed for Ni deposited into porous silicon templates [43,46]. …”

MOKE Magnetometer Studies of Evaporated Ni and Ni/Cu Thin Films onto Different Substrates

“…The physical properties of thin films strongly depend on the method and the conditions of deposition, on the substrate, and the film thickness. Several works have been reported on Ni films [6][7][8][9][10][11][12] and on the Ni/Cu/substrates bilayers [13,14]. Among the effect of Ni thickness on the physical properties, one may cite (i) the transition from an out-of plane to an in-plane magnetization easy axis, (ii) the effect of the lattice strain on the magnetic moment reduction and (iii) the change from a fine grain structure to a column structure [15][16][17][18].…”

Structure transition and magnetism of bcc-Ni nanowires

“…[4][5][6][7] As a traditional ferromagnetic transition metal, nickel has been intensively studied for its ferromagnetic properties in powders, lms, and nanowires. [8][9][10][11][12][13][14][15] It is known that a face-centered-cubic (fcc) nickel structure has better stability in bulk, whereas hexagonal closed-packed (hcp) and body-centered-cubic (bcc) nickel structures are metastable in bulk and do not exist naturally. However, as the grain size of these metals gets small, into the nano-scale, with an increasing ratio of surface atoms, their structures and magnetic properties make sudden changes at some critical points.…”

“…For example, the hcp-Ni phase has been detected in some synthesized nickel structures. [16][17][18] Non-naturally occurring bcc Ni lm has been achieved by Heinrich et al 19 and also conrmed independently by Wang et al 20 Ferromagnetism in fcc-Ni nanowires 14,15 and hcp-Ni nanowires 18,27 is well acknowledged, but the magnetic properties of bcc-Ni are still under experimental research [19][20][21] and theoretical calculation. [22][23][24][25][26] The possible existence of weak itinerant ferromagnetism in bcc-Ni lms prepared under compression is predicted by Khmelevskyi et al 24 A crucial step forward in experiments was successful preparation of bcc-Ni on GaAs (001) by Tian et al, 21 and it was proven that the bcc-Ni is ferro-magnetic with a Curie temperature of 456 K. These pioneering results have opened up a unique opportunity for investigation of the puzzling problem that is whether Ni exists as a meta-stable structural phase or not in nature.…”