Coherent Ferromagnetic Precipitate and Anomalies in the Heat Conduction and Thermopower of Mn$\text{}_{2-x}$Cr$\text{}_{x}$Sb Single Crystals

The heat diffusivity D, the electrical resistivity ρ and the thermoelectric power S of tetragonal Mn$\text{}_{2-x}$Cr$\text{}_{x}$Sb single crystals with 0.02 < x < 0.12 have been measured in the temperature range of 90 K < T < 350 K and along different crystal axes. The heat conductivity κ and σ = 1/ρ are anisotropic along the crystal axes a, c with a ratio of 2:1. κ(T) , ρ(T) and S(T) show anomalies at the spin reorientation temperature T$\text{}_{Rm}$ of the matrix (M) Mn$\text{}_{2-x}$Cr$\text{}_{x}$Sb, but also at that of the coherent ferromagnetic precipitate (P) Mn$\text{}_{1.037}$Cr$\text{}_{0.11}$Sb, T$\text{}_{R_{p}}$ which is assigned to variations in the spin dependent scattering at the M /P interfaces via changes in the relative orientation of the magnetization vectors of matrix and precipitate (spin valve effect).