The similar dependence of the magnetocaloric effect and magnetoresistance in TmCu and TmAg compounds and its implications

We report the results of resistivity (p), magnetoresistance (MR) and in-fie ld heat capacity (C) measurements on TmCu and TmAg compounds. Despite the d ifferent nature of magnetic transitions-first-order in TmCu and second-orde r in TmAg-the magnetocaloric effect (MCE) obtained from in-field heat capac ity data is similar for higher fields. There are striking similarities betw een the MCE and MR as a function of temperature as well as magnetic field ( H). We have shown that in the paramagnetic state, MCE has -H-2 dependence d ue to the suppression of spin fluctuation. Since the MCE and MR are related with thermodynamic and transport properties respectively, two different pr operties of a system and the similarities between the two indicate a deeper relation between the origin of MR and MCE.