Theoretical characterization of NdPd material for cryogenic cooling applications

Abstract

In this investigation, we have conducted a comprehensive analysis of NdPd compound, focusing on its fundamental properties, magnetic behavior, and potential for magnetocaloric applications. The approach involved a combination of ab-initio calculations and MCs. Notably, the computed magnetic moment for the Nd atom stands at 3.11µ B , close to the experimental value. Moreover, the exchange couplings of Nd-Nd interactions have unearthed intriguing insights: the initial two exchange couplings ( J 1 = 1.593 meV and J 2 =-0.358 meV) exhibit positive signs, indicative of ferromagnetic tendencies. Another result from our simulations is the discovery of ferromagnetic ordering within the NdPd compound, which takes place at a critical temperature ( T c of 16K. Additionally, we observed the isothermal magnetic entropy in a 5T magnetic field around the Curie temperature, exhibiting remarkable agreement with laboratory results. This discovery implies that utilizing NdPd for magnetic refrigeration can show significant potential for effectively cooling cryogenic systems operating within temperatures below 20K.