Short-range magnetic correlations enhanced magnetocaloric effect in the rare-earth germanide: Dy2Co3Ge5

Abstract

In this work, the structural, magnetic, thermal, and magnetocaloric properties of the rare-earth germanide Dy2Co3Ge5 are explored in detail. Structural analysis confirms that the compound crystallizes in the Lu2Co3Si5-type structure with the monoclinic space group I12/c1. The antiferromagnetic Dy2Co3Ge5 exhibits a complex magnetic behavior, showing successive antiferromagnetic transitions at 32, 25, and 19 K, where the transitions at 32 and 25 K are of second order, and the transition at 19 K is of first-order nature. A field-induced metamagnetic transition is observed near 30 kOe in the low-temperature antiferromagnetic regime. Additionally, in the paramagnetic region up to approximately 85 K, significant short-range ferromagnetic correlations are evident, possibly arising from an induced magnetic moment on Co atoms by Dy. Magnetocaloric measurements reveal an inverse magnetocaloric effect below 25 K and a conventional magnetocaloric effect above 25 K. Notably, Dy2Co3Ge5 exhibits superior magnetocaloric performance compared to its terbium analog Tb2Co3Ge5.