Investigation of magnetic and electrical transport properties of Dy_2Ni_2Sn

摘要

The magnetic and transport properties of the ternary rare-earth compound Dy_2Ni_2Sn are reported. The compound undergoes a long range antiferromagnetic ordering below T_N=43 K with a collinear structure. A second transition is observed below about T_t=28 K, where spin canting takes place. We find clear thermal hysteresis in our magnetization data between 20 and 45 K, indicating the first order nature of the magnetic transitions occurring at T_N and T_t. Clear signature of metamagnetism is observed in the canted antiferromagnetic phase. The change in entropy on the application of magnetic field (magnetocaloric effect) was calculated from the isothermal magnetization data and it shows negative and positive peaks at T_N and T_t respectively. The thermal variation of resistivity shows clear peak like signature near T_N, which gets suppressed under applied magnetic field resulting negative magnetore-sistance. The low temperature resistivity (below T_t) can be well fitted with the model available for spin dependent s-f scattering in antiferromagnetic system having well localized moments. The data also indicate short range correlations well above the antiferromagnetic transition point, which might be related to the two dimensional spin-spin correlations in this layered compound.