Glassy magnetic ground state and Kondo-like behaviour in Mn₁₀FeGe₈alloy

Abstract

We report detailed investigation on the ground-state magnetic properties of newly synthesized Mn10FeGe8 alloy. The sample can be thought of being derived by substituting one Mn atom by Fe of the parent compound Mn11Ge8. Fe-substitution leads to drastic change in the magnetic ground state as well as to the magnetotransport properties of the parent alloy. On cooling below 250 K,Mn10FeGe8 undergoes a transition from paramagnetic phase to a state having significant ferromagnetic correlations. The ground state is found to be canonical spin glass (CSG) type in nature as evident from the dc magnetization and ac susceptibility measurements. Interestingly, the resistivity data shows an upturn at low temperature below about 30 K mimicking the Kondo-like behaviour. Mn10FeGe8 is turned out to be a rare example among 3d transition metal alloys, where a Kondo like state coexists within a CSG phase.