Dynamic domain motion of thermal-magnetically formed marks on CoNi∕Pt multilayers

Abstract

We characterized a method of heat-assisted magnetic recording, which is potentially suitable for probe-based storage systems. The field emission current from a scanning tunneling microscope tip was used as the heating source. Various pulse voltages were applied to two types of CoNi/ Pt multilayered films: one is strongly coupled with low coercivity, and the other is weakly coupled with high coercivity. Experimental results show that marks achieved in strongly coupled medium are larger than that in granular one. An external magnetic field was then applied to those marks. For weak fields ͑lower than the coercivity of the medium͒ the size of marks changes distinctly in the strongly coupled medium but not in the granular one. A model of magnetic domain dynamics is built to quantitatively explain the experimental results. It agrees with experiments. Based on this model, we will be able to figure out the proposals to achieve small marks for ultrahigh recording density.

Magnetic and Magnetoresistive Properties of 3D Interconnected NiCo Nanowire Networks

“…In this work, we demonstrate the suitability and reliability of using CNWs of different magnetic materials to obtain tunable magnetoresistive behavior. Interconnected NW networks made of electrodeposited NiCo alloys were chosen for the present study because of the interest in these alloys for a wide variety of applications, including magnetic storage systems [ 16 , 17 ], magnetic and microresonator sensors [ 18 , 19 ], fuel cells [ 20 ], microelectromechanical systems (MEMS) [ 21 ], hydrogen storage [ 22 ], and materials as catalysts [ 23 ]. It is shown that magnetic alloy CNWs of controlled composition can be easily obtained through careful control of the deposition potential and using different electrolytic solutions.…”

A study on the synthesis of Ni50Co50 alloy nanostructures with tuned morphology through metal–organic chemical routes

“…8 Such bimetallic materials could find applications in high-temperature electrochemical devices, such as solid oxide fuel cells (SOFCs), 9 in electromagnetic devices (such as magnetic recording devices) as well as in ferrofluid dynamotors and magcards. 10,11 Moreover, the NiCo alloy is known to be highly active for methane dry reforming, and this advantageously promotes the catalyst stability by inhibiting coke formation. 12 The 'polyol' reduction approach has been widely reported in the literature for the formation of both spherical and anisotropic NiCo alloy particles.…”

Controlled synthesis, phase formation, growth mechanism, and magnetic properties of 3-D CoNi alloy microstructures composed of nanorods

“…16 These properties of CoNi have been used for promising applications like microwave absorption, solid oxide fuel cells, 17 biomedical microdevices, 18 catalysis, 19 microelectromechanical systems (MEMS), 20 and magnetic recording. 21,22 In the recent years, many micro and nanostructures of CoNi alloys have been prepared including multilayer stacked alloy plates, 1-D magnetic chains, 23,24 Ni 7 Co 3 Nanoring, 25 handkerchief like Ni 82 Co 18 , 26 nanowires, [27][28][29][30] Co 50 Ni 50 nano dumbbells, 31 Co 81 Ni 19 nanotubes, 32 hollow CoNi submicrospheres, 33 flowery, 34 Ni 33.8 Co 66.2 dendrites, 19 spherical Co x Ni 1002x nanoparticle, 35 and CoNi thin films. 36,37 Several methods have been applied to synthesize CoNi alloy nanostructures such as polyol process, 25,27,31,35 hydrothermal/solvethermal, 19,23,24,33 double composite temple approach, 26 mechanical alloying, 38 electrodeposition, 28,29,32 non-aqueous ethylene glycol refluxing, 36 chemical vapor deposition 37 etc.…”