Fabrication of single crystalline, uniaxial single domain Co nanowire arrays with high coercivity

Abstract

Whilst Co nanorods with high coercivity were synthesized during recent years, they did not achieve the same results as for Co nanowires embedded in solid templates. In the present work, Co nanowire arrays (NWAs) with high coercivity were successfully fabricated in porous aluminum oxide template under optimum conditions by using pulsed ac electrodeposition technique. Magnetic properties and crystalline characteristics of the nanowires were investigated by hysteresis loop measurements, first-order reversal curve (FORC) analysis, X-ray diffraction (XRD), and selected area electron diffraction (SAED) patterns. Hysteresis loop measurements showed high coercivity of about 4.8 kOe at room temperature together with optimum squareness of 1, resulting in an increase of the previous maximum coercivity for Co NWAs up to 45%. XRD and SAED patterns revealed a single crystalline texture along the [0002] direction, indicating the large magnetocrystalline anisotropy. On the other hand, FORC analysis confirmed a single domain structure for the Co NWAs. In addition, the reversal mechanism of the single crystalline, single domain Co NWAs was studied which resulted in the fixed easy axis with a coherent rotation. Accordingly, these nanowires might offer promising applications in high density bit patterned media and low power logic devices.

Tailoring magnetic properties in arrays of pulse-electrodeposited Co nanowires: The role of Cu additive

“…This is because that, the control over geometrical parameters such as the length and diameter of magnetic NWs leads to tuning of magnetic properties, offering a variety of applications ranging from high density magnetic recording media to high quality sensing and microwave devices [5][6][7]. Besides, it provides an interesting research field for the investigation of different magnetic mechanisms including magnetization reversal behavior and magnetic interaction processes which, in turn, can provide new insights into the applications concerned [5,8,9]. In this way, if the tunable properties are achieved through new and simple approaches, they will be of significant importance.…”

Quantitative study of FORC diagrams in thermally corrected Stoner– Wohlfarth nanoparticles systems

“…Substituting equation (7) in (8) and tacking into account equation (9) ( ̃ ) ( ) ( ) , it is possible to factorize the integral of equation (8), despite of is function of V and K through , which leads to the following expression:…”

“…The use of FORC diagrams became a frequently used tool to study different kind of magnetic systems [1][2][3][4][5][6][7][8][9][10][11][12]. As this method provides more information than conventional hysteresis cycles from the same type of experiment, its use has been increased considerably in recent years.…”

Artificially modified magnetic anisotropy in interconnected nanowire networks

“…Furthermore, tuning of their magnetic properties can be done by adjusting electrodeposition conditions, such as bath temperature, 8 deposition potential, [9][10][11] electrolyte composition and pH value. 12 There are several strategies to modify the NW arrays in order to produce materials that differ from the parallel array of homogeneous nanowires.…”