Study of magnetization reversal of uniaxial Ni nanodots by magnetic force microscopy and vibrating sample magnetometer

Abstract

In this work we report on the study of magnetization reversal in zero dimensional nickel nanodots patterned using a novel polymer based soft lithography technique. The nanodots, having their easy axis of magnetization normal to the plane of the sample, were characterized by in situ MFM observations, performed under varying magnetic fields to understand the magnetization reversal process. The average demagnetization curve of the sample was obtained from the MFM images. The results compare well with the demagnetization curve obtained from vibrating sample magnetometer (VSM) measurements. Further, the angular dependence of in-plane magnetization reversal process was investigated by studying the magnetization data obtained from the VSM performed at different angles of field orientation with respect to the sample.

Evolution of coercivity and its angular dependence in CoFe nanostructures subjected to field cooling

“…It can be seen that there is an easy axis of magnetization parallel to the substrate plane. This is typical of as‐deposited magnetic ultrathin films …”

“…In a previous work, we have investigated the angular dependence of magnetization in ferromagnetic nanostructures of nickel. There are also other works reporting the angular dependence of coercivity in different kinds of magnetic thin films and nanostructures .…”

Effect of an external magnetic field on the morphology and magnetic properties of CoFe nanostructures

“…The above observations indicate the significance of an external magnetic field during the growth of CoFe magnetic nanostructures. The relative orientation of the easy axis of magnetization with respect to the substrate plane is an important factor in the application of CoFe and similar magnetic systems in high density data storage media 1–3, 7. It is evident that, having a calibrated external magnetic field with a suitable orientation can be used as one another method 12 of controlling the size and magnetic orientation of the nanostructures in such systems.…”

“…The synthesis of metallic monolayers and multilayers of ferrous group metals is of great interest because of their magnetic properties. They have found wide application in the field of magnetic data storage, especially for reading/writing elements in the hard drive heads 1–3. Numerous investigations have been carried out related to the vapor phase deposition of ferrous alloys.…”

Magnetization Reversal in Different Magnetic Thin Films Studied Using a Magnetic Actuator

“…There are many methods for studying the magnetization reversal of magnetic thin films: the use of a magnetoresistance, 1,2) magnetic force microscope (MFM), 3,4) a vibrating sample magnetometer (VSM), 5) the magneto-optical Kerr effect (MOKE), 6,7) and a superconducting quantum interference device (SQUID). 8) However, the magnetic behavior of ferromagnetic thin films is studied by using a magnetic actuator in this study.…”