STUDIES ON SPIN DYNAMICS IN DOPED URU2SI2

We present muon relaxation studies on two doped URu2Si2-based compound s - (U0.95La0.05)Ru2Si2 and (U0.5Y0.5) Ru2Si2. In the 5% La doped samp le, we found the time dependence of muon spin depolarisation rather si milar to our previous observations on (U0.95Y0.05)Ru2Si2. Surprisingly , similar behaviour has also been shown in our work on (U0.5Y0.5)Ru2Si 2. The onset temperatures of magnetic order from mu SR agree well with our conclusions from previous transport and thermodynamic studies tha t a magnetic order parameter develops at 14 and 17 K for 5% La and 50% Y doped samples respectively and as in pure URu2Si2 never saturates d own to 5 K. Comparisons will be made with previous studies on URu2Si2 and other doped URu2Si2.