Paramagnons in heavy-electron systems

Paramagnons in heavy-electron systems are theoretically examined. First, local spin fluctuations are fully included in the best single-site approximation. A local Kondo temperature is uniquely defined to show a characteristic energy scale of local spin fluctuations. Secondly, paramagnons are included perturbatively. Such a theory is applied to analyze the specific-heat data of heavy-electron compounds such as ${\mathrm{UAl}}_2$, ${\mathrm{UPt}}_3$, and ${\mathrm{CeSi}}_{1.85}$, where anomalous ${\mathit{T}}^3$lnT terms are observed at low temperatures T${\mathit{T}}^3$lnT terms.