Special Issue on Nanoscience and Technology (ICONSAT 2010); Edited by D. Bahadur, Satish Vitta and A. K. SoodNo Access

TEMPERATURE DEPENDENT COERCIVITY AND RELAXATION PHENOMENA IN AMORPHOUS Fe–(Mn)–Zr–B NANOPARTICLES

DEBABRATA MISHRA

Department of Physics, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India

Search for more papers by this author

A. PERUMAL

Department of Physics, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India

Search for more papers by this author

, and

A. SRINIVASAN

Department of Physics, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India

Search for more papers by this author

https://doi.org/10.1142/S0219581X11008435Cited by:2 (Source: Crossref)

Abstract

We report the temperature dependent coercivity behavior and the improvement of room temperature soft magnetic properties in interacting amorphous Fe–Mn–Zr–B powder nanoparticles prepared by mechanical alloying of elemental powders. With increasing Mn concentration from 5 to 20 at.% in Fe–Zr–B alloys, the coercivity (H_C) reduces drastically from 170 to 25 Oe. Temperature dependent H_C behavior shows exponential variation of H_C with temperature. Interparticle interactions dominate the low temperature behavior and surface effect on the nanoparticles is more pronounced at low temperatures. Magnetic relaxation behavior shows slow relaxation in the interacting amorphous nanoparticles and the relaxation process is observed to be thermally activated in the present studies.

Keywords:

References

G. Bertotti , Hysteresis in Magnetism ( Academic Press , USA , 1998 ) . Crossref, Google Scholar
G. Herzer, IEEE Trans. Magn. 25, 1397 (1990). Google Scholar
D. Mishra, A. Perumal and A. Srinivasan, J. Phys. D: Appl. Phys. 41, 215 (2008), DOI: 10.1088/0022-3727/41/21/215003. Web of Science, Google Scholar
M. M. Ricoet al., J. Nanosci. Nanotechnol. 8, 2858 (2008). Crossref, Web of Science, Google Scholar
T. Miyazakiet al., J. Magn. Magn. Mater. 60, 211 (1986). Crossref, Web of Science, Google Scholar
D. Fioraniet al., Physica B 320, 122 (2002), DOI: 10.1016/S0921-4526(02)00659-2. Crossref, Web of Science, Google Scholar
Y. X. Bo and T. Miyazaki, J. Magn. Magn. Mater. 86, 37 (1989). Web of Science, Google Scholar
E. D. Biasiet al., Phys. Rev. B 71, 104408 (2005). Crossref, Web of Science, Google Scholar
D. R. Cornejo, A. M. Boudri and J. M. Aquimo, Phys. Rev. B 320, 270 (2002). Google Scholar
A. Labartaet al., Phys. Rev. B 48, 10240 (1993), DOI: 10.1103/PhysRevB.48.10240. Crossref, Web of Science, Google Scholar
J. A. Mydosh , Spin Glasses: An Experimental Introduction ( Taylor and Francis , New York , 1993 ) . Google Scholar
M. Foldeaki, L. Koszegi and R. A. Dunlap, Philos. Mag. B 63, 1101 (1991) . Google Scholar