Study of hard-soft magnetic ferrite films prepared by pulsed laser deposition

M Satalkar,D M Phase,A Pasko,R J Chaudhary,S Raghuvanshi,M Lobue,N Ghodke,P Tapkir,F Mazaleyrat,S N Kane,A Ghosh

doi:10.1088/1742-6596/534/1/012043

Abstract

Soft magnetic Mg0.1Ni0.3Zn0.6Fe2O4 and hard magnetic BaFe12O19 bulk nanocrystalline ferrites were synthesized using the sol-gel auto-combustion method, and were used as targets to deposit soft-hard thin films by the pulsed laser deposition (PLD) method. Various soft-hard thin films with different preparation conditions were deposited on Si (100) substrate, which can be effectively utilized to get better magnetic properties. The prepared films were characterized by the X-ray diffraction (XRD), atomic force microscopy (AFM) and magnetic measurements. XRD confirms the presence of soft and hard phases in the thin films. Coercivity of the prepared films ranges from 1.67 to 2.66 kA/m. AFM images show clustering of grains at the film surface with a characteristic columnar growth.

Highlights

Exchange spring systems have stimulated intense research activities in the recent years because of the prediction of improvement in the magnetic properties of these systems [1–2]
The BaFe12O19 ferrite serves as a hard phase and the Mg0.1Ni0.3Zn0.6 ferrite as a soft phase in the hard-soft composite used for depositing the exchange spring magnet on Si (100) substrate
X-ray diffraction (XRD) validates the formation of a single-phase cubic spinel structure, magnetic measurements prove the soft magnetic nature of this powder

Summary

Introduction

Exchange spring systems have stimulated intense research activities in the recent years because of the prediction of improvement in the magnetic properties of these systems [1–2]. In the nanocomposite exchange spring media, two magnetically hard layers and a magnetically soft layer are strongly exchange coupled, which can be achieved by their crystallographic coherence [3]. This in turn combines high magnetization of the soft phase with high coercivity of the hard phase, and is determined by the distribution of hard and soft magnetic phases [4]. The objective of the present work is to get the appropriate preparation conditions for depositing soft-hard composite films by the pulsed laser deposition (PLD) and to use them to obtain improved magnetic properties (higher coercivity and magnetization) in the studied composite magnets. The composite of hard and soft ferrites was prepared by mixing of the individual ferrite components in a ratio of 2:1.

Objectives

Results

Conclusion