Magnetic properties of R$_{2}$TIn$_{3}$ (R= Nd,Ho,Er; T= Cu,Ag) compounds by $\mu$ SR

The ternary R$_{2}$TIn$_{3}$ alloys crystallize in binary type crystal structures where the R ions occupy one site, while T and In ions shares the other site in random occupation. This disorder together with competing antiferromagnetic nearest neighbour and ferromagnetic next-nearest neighbour exchange leads to magnetic frustration. From susceptibility antiferromagnetic order with T$_{N }$in the 10K range was proposed. Subsequent neutron diffraction did not detect magnetic Bragg peaks. The present $\mu $SR data show that below the susceptibility peak temperatures the spin systems freeze into an only short-range ordered structure, long-range order being definitely absent. Persistent spin fluctuations were present in the limit T$\diamondsuit $0, a feature often observed by $\mu $SR in frustrated magnetic materials.