Giant magnetoresistance and table-like magnetocaloric effect in double perovskite oxide PrSrMnCoO_6

摘要

Magnetoresistance and magnetocaloric effect of a double perovskite oxide PrSrMnCoO_6 (cubic, Fm3m) has been studied in fields up to 7 T. This compound is semiconductor-like and its electrical resistivity increases by 5 orders while going from 300 to 50 K. Giant magnetoresistance of ~40% is observed at 200 K in 7 T field. PrSrMnCoO_6 orders ferromagnetically at ~150 K and shows a maximum magnetic entropy change of ~4.6 J/kg/K for 5 T field change in the temperature range of 110-190 K. This nearly constant magnetocaloric effect over a broad temperature span is highly suitable for Ericsson-cycle magnetic refrigeration.