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Coupled atomic motion and spin-glass transition in FeAl2

Yang Li·F. G. Vagizov·V. Goruganti·Joseph H. Ross, Jr.·Zuxiong Xu·Guohui Cao·Cheng Dong·Zhaosheng Feng
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Abstract

We have used 57Fe Mossbauer spectroscopy and x-ray diffraction to study the magnetic and vibrational properties of FeAl2. FeAl2 is an ordered intermetallic with a large Fe local moment, and a complex crystal structure with site-occupation disorder on some sites. This material exhibits spin-glass freezing below 35 K. From the 57Fe recoilless fraction, we find that there is a vibrational mode which freezes out concurrently with the spin freezing. X-ray powder diffraction measurements confirm this result, indicating an anomalous change in the Debye-Waller factor at temperatures below the spin-freezing temperature.

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Yang Li, F. G. Vagizov, V. Goruganti, Joseph H. Ross, Jr., Zuxiong Xu, Guohui Cao, Cheng Dong, Zhaosheng Feng. 2005-02-25. Coupled atomic motion and spin-glass transition in FeAl2. https://arxiv.org/abs/cond-mat/0308471

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