Spin-Wave Thermal Conductivity of Ferromagnetic EuS

摘要: Experimental and theoretical investigations have been made of the spin-wave thermal conductivity ferromagnet europium sulfide. Measurements from 1.5-4\ifmmode^\circ\else\textdegree\fi{}K on compressed powders. The temperature dependence below 4\ifmmode^\circ\else\textdegree\fi{}K has calculated for several external magnetic fields, assuming boundary scattering considering first- second-neighbor interactions. With no field, experimental can be approximately represented by $\mathcal{K}=1.2{T}^{2}$ mW/cm(\ifmmode^\circ\else\textdegree\fi{}K) which is reasonably close to dependence. However, an field 9 kG produced a drop in ranging 2 or 3% at 25% 1.5\ifmmode^\circ\else\textdegree\fi{}K; according theory should decrease 11% 31% 1.5\ifmmode^\circ\else\textdegree\fi{}K. This disagreement between experiment quite marked higher temperatures will require further study its resolution.