Magnetic structure of RuSr2(Eu1.5Ce0.5)Cu2O10−δ studied by 119Sn-Mössbauer spectroscopy

We report on the results of 119Sn-Mössbauer measurements performed between room temperature and 4.2 K on a series of doped (Ru1−xSnx)Sr2(Eu1.5Ce0.5)Cu2O10−δ samples (with x = 0.02, 0.04 and 0.06) (so called 1222-type). The spectral analysis suggests that Sn substitutes Ru5+ at the RuO2 layers, and enters as Sn4+. We observe for the 4.2 K Mössbauer measurements that an in-plane transferred hyperfine field (hf) exists at the Sn(Ru) site in the (Ru,Sn) O2 layers. The value of the average hf field decreases with increasing Sn concentration from 3.64 T (for x = 0.02) to 2.62 T (for x = 0.06).