Thermal hysteresis and domain states in Ni–Zn ferrites synthesized by oxalate precursor method

• Published in: Journal of magnetism and magnetic materials 2010-07, Vol.322 (14), p.1999-2005
• Main Authors: Chaudhari, N.D., Kambale, R.C., Bhosale, D.N., Suryavanshi, S.S., Sawant, S.R.
• Format: Article
• Language: English
• Subjects: a.c. susceptibility; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Domain effects, magnetization curves, and hysteresis; Domain states; Exact sciences and technology; Ferrites; Hysteresis studies; Magnetic properties; Magnetic properties and materials; Magnetism; Magnetization curves, magnetization reversal, hysteresis, barkhausen and related effects; Nickel; Ni–Zn ferrite; Oxalate precursor; Oxalates; Physics; Precursors; Saturation (magnetic); Zinc
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2010.01.022

Nickel zinc ferrites with generic formula, Ni X Zn 1− X Fe2O4 (with X=0.28–0.40) were synthesized by an oxalate precursor route starting with acetates to study their magnetic properties. The saturation magnetization versus temperature curves resemble those of R type ferrites. The system shows the presence of Yafet–Kittel type of spin. It is observed that magnetic moment ( n B ) values increase with the addition of Ni 2+. The remanance ratio R tends to increase with the addition of Ni 2+, which has been attributed to the increase of magnetocrystalline anisotropy constant (K1). The values of R compare well with the theoretical value (0.87). The coercive force ( H c ) tends to increase with the addition of Ni 2+, which has been related to the reverse domain formation. Studies on temperature variation of R and H c reveal that these parameters are thermally insensitive, which confirms the presence of multi domain grains in the material. These observations have been supported by a.c. susceptibility studies.