Mean-field heat capacity of dilute magnetic alloys

J. Mackowiak

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Mean-field heat capacity of dilute magnetic alloys

J. Mackowiak

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Abstract

Using an asymptotic solution of the M-impurity thermodynamics of a dilute s-d system, the impurity energy and impurity heat capacity DeltaC(T) are derived for dilute magnetic alloys with spin 1/2 and spin 3/2 impurities. The parameters which enter DeltaC are adjusted to fit experimental data on impurity heat capacity of CuCr and LaCeAl_2. Agreement is satisfactory for CuCr, at temperatures below 1K, and good for LaCeAl_2. The magnitude of theoretical DeltaC(T) agrees with experiment and does not require scaling as in previous s-d theories. Nonlinear dependence of DeltaC(T) on impurity concentration has been accounted for the first time.

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J. Mackowiak. 2007-03-06. Mean-field heat capacity of dilute magnetic alloys. https://arxiv.org/abs/cond-mat/0703146

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