Eleventh International Conference on Internal Friction and Ultrasonic Attenuation in Solids
J. Phys. IV France 06 (1996) C8-651-C8-654
Low Temperature Magnetoelasticity and Internal Friction of an Amorphous Reentrant Spin GlassE. Gaganidze, A. Setzer and P. Esquinazi
Dept. Superconductivity and Magnetism, University of Leipzig, Linnéstrasse 5, 04103 Leipzig, Germany
We have studied the magnetomechanical behavior of the amorphous metal METGLAS 2826A (Fe32Ni36Cr14P12B6) in the as-quenched and annealed states at temperatures 50mK<T<10K, magnetic fields B<3T and at frequencies <3kHz. The alloy is ferromagnetic below 240K and shows a reentrant spin glass transition at Tf = 1.2K. The acoustic properties in the as-quenched and in the early stage of annealing states show strong anomalies at the spin glass transition. These anomalies vanish for a field of 0.07 T applied parallel to the main surface of the sample. Due to demagnetization effects the field dependence of magnetoelastic properties at Tf depends strongly on the angle between magnetic field and main surface of the sample. We show that the "Giant Δ E effect" observed in this sample is a consequence of the macroscopic magnetization of the sample. The sample in the amorphous and partially crystallized states shows no glasslike behavior in the acoustic properties which is usually observed in amorphous and polycrystalline metals.
© EDP Sciences 1996