Three-dimensional critical behavior and magnetocaloric effect in Yb14MnSb11

Systematic investigations were performed on the nature of the magnetic properties of Yb ₁₄MnSb ₁₁, which is the first ferromagnetic Kondo lattice compound in the underscreened limit and one of the highest thermoelectrically efficient materials with p -type conduction. The Rhode-Wohlfarth ratio (RWR) is estimated to be 1.01, which demonstrates the localized nature of the ferromagnetism in Yb ₁₄MnSb ₁₁, consistent with the predicted Ruderman–Kittel–Kasuya–Yosida (RKKY) like exchange interaction. Detailed analyses on critical behavior indicate a second-order ferromagnetic phase transition with critical exponents β = 0.307(2), γ = 0.923(9), and δ = 4.003(4), demonstrating a three-dimensional critical behavior with long-range interaction. Furthermore, the magnetocaloric effect and relative cooling power are estimated to be 0.772 J kg ⁻¹ K ⁻¹ and 16.43 J kg ⁻¹ at 5 T, respectively. The magnetic transition temperature of T C = 51.9(3) K is strictly estimated by evaluating the magnetic change of specific heat [ Δ C p ( T , H ) ]. The rare d -electron ferromagnetic Kondo lattice, small magnetocaloric effect, and high-temperature large thermoelectric efficiency making Yb ₁₄MnSb ₁₁ to be a system of considerable interest.