Magnetic anisotropy and phase transitions in single-crystal Tb5(Si2.2Ge1.8)

Date
2005-05-16
Authors
Han, M.
Snyder, J.
Tang, W.
Lograsso, Thomas
Schlagel, Deborah
Jiles, David
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Abstract

The Tb5(SixGe4−x) alloy system has many features in common with the Gd5(SixGe4−x)system although it has a more complex magnetic and structural phase diagram. This paper reports on the magnetic anisotropy and magnetic phase transition of single-crystalTb5(Si2.2Ge1.8) which has been investigated by the measurements of M-H and M-T along the a, b, and c axes. The variation of 1/χ vs T indicates that there is a transition from paramagnetic to ferromagnetic at Tc = 110 K. Below this transition temperature M-Hcurves show very strong anisotropy, and it is believed that this is due to the complex spin configuration. M-H measurements at T = 110 K show that the a axis is the easy axis, and that the saturation magnetization is 200 emu/g. The b axis is the hard axis, which needs an external magnetic field much higher than 2 T to saturate the magnetization in that direction, indicating a high magnetocrystalline anisotropy. The c axis is of intermediate hardness. The magnetic properties of this material are therefore very different from those of the related Gd5Si2Ge2 system, in which the b axis was found to be the easy axis and the magnitude of the anisotropy was smaller.

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Copyright 2005 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.

This article is from Journal of Applied Physics 97 (2005): 10M313 and may be found at http://dx.doi.org/10.1063/1.1855196.

Keywords
Materials Science and Engineering, Electrical and Computer Engineering, terbium alloys, silicon alloys, germanium alloys, paramagnetic materials, ferromagnetic materials, magnetic anisotropy, ferromagnetic-paramagnetic transitions, magnetic hysteresis, magnetic moments, Curie temperature
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