2007/03/08 by K. Berggold, J. Baier, D. Meier +8
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Art #Humanities #Magnetic and transport properties of perovskites and related materials #Multiferroics and related materials #Physics #Thermal conductivity #Thermodynamics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.76.094418
published as Physical Review B 76, 094418 (2007) · 9 pages including 6 figures
arxiv created 2007/03/08 · openalex publication_date 2007/09/26 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present measurements of the thermal conductivity \ensuremathκ and the thermal expansion \ensuremathα of NdMnO3 and TbMnO3. In both compounds, a splitting of the 4f multiplet of the R3+ ion causes Schottky contributions to \ensuremathα. In TbMnO3 this contribution arises from a crystal-field splitting, while in NdMnO3 it is due to the Nd-Mn exchange coupling. Another consequence of this coupling is a strongly enhanced canting of the Mn moments. The thermal conductivity is greatly suppressed in both compounds. In TbMnO3, the main scattering process is resonant scattering of phonons between different energy levels of the 4f multiplets, whereas the complex 3d magnetism of the Mn ions is of minor importance. In NdMnO3, resonant phonon scattering on the 4f levels dominates at low temperature, while scattering on magnetic excitations becomes important at higher temperature.