2025/12/22 by V. Yu. Irkhin, Irkhin, Valentin Yu., Zhehong Liu +9
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci) #Rare-earth and actinide compounds #Strongly Correlated Electrons (cond-mat.str-el)
paper · doi:10.48550/arxiv.2512.19384
openalex publication_date 2025/12/22 · openalex created_date 2025/12/24 · openalex updated_date 2026/07/28
Experimental data on the specific heat Cp of quadruple perovskites ACu3Fe2Re2O12 (A = Mn, Cu, La, Ce, Dy) are presented, demonstrating an anomalous concave-down Cp/T vs. T2 curve and a bell-shaped feature in β(T) = (Cp - γT)/T3 plotted against T on a logarithmic scale. This feature is most pronounced for A = Cu and Mn. These findings can be explained by the rattling phenomenon, previously identified in other systems such as filled skutterudites and β-pyrochlores. Using first-principles DFT+U calculations, the presence of a rattling mode in A = Mn system is directly confirmed. A qualitative interpretation of the rattling mechanism in terms of a pseudo-Jahn-Teller effect is proposed.