Muon spin relaxation study on itinerant ferromagnet CeCrGe₃and the effect of Ti substitution on magnetism of CeCrGe₃

A Muon spin relaxation (μSR) study has been performed on the Kondo lattice heavy fermion itinerant ferromagnet CeCrGe₃. Recent investigations of bulk properties have revealed a long-range ordering of Cr moments at T_c = 70K in this compound. Our μSR investigation between 1.2K and 125K confirm the bulk magnetic order which is marked by a loss in initial asymmetry below 70K accompanied with a sharp increase in the muon depolarization rate. Field dependent μSR spectra show that the internal field at the muon site is higher than 0.25 T apparently due to the ferromagnetic nature of ordering. The effect of Ti substitution on the magnetism in CeCrGe₃ is presented. A systematic study has been made on polycrystalline CeCr_1-xTi_xGe₃ (0 ≤ x ≤ 1) using magnetic susceptibility χ(T), isothermal magnetization M(H), specific heat C(T) and electrical resistivity ρ(T) measurements which clearly reveal that the substitution of Ti for Cr in CeCrGe₃ strongly influences the exchange interaction and ferromagnetic ordering of Cr moments. The Cr moment ordering temperature is suppressed gradually with increasing Ti concentration up to x = 0.50 showing T_c = 7K beyond which Ce moment ordering starts to dominate and a crossover between Cr and Ce moment ordering is observed with a Ce moment ordering T_c = 14K for x = 1.0. The Kondo lattice behavior is evident from temperature dependence of ρ(T) in all CeCr_1-xTi_xGe₃ samples.