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Excitations in Spin Chains and Specific-Heat Anomalies in Yb(4)As(3)

Burkhard Schmidt·Peter Thalmeier·Peter Fulde
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Abstract

An explanation is given for the observed magnetic-field dependence of the low-temperature specific heat coefficient of Yb(4)As(3). It is based on a recently developed model for that material which can explain the observed heavy-fermion behaviour. According to it the Yb(3+)-ions are positioned in a net of parallel chains with an effective spin coupling of the order of J = 25 K. The magnetic-field dependence can be understood by including a weak magnetic coupling J' between adjacent chains. The data require a ratio J'/J of about 10^{-4}. In that case the experimental results can be reproduced very well by the theory.

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Burkhard Schmidt, Peter Thalmeier, Peter Fulde. 1996-03-08. Excitations in Spin Chains and Specific-Heat Anomalies in Yb(4)As(3). https://doi.org/10.1209/epl%2Fi1996-00540-7

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