Magnetic and magnetocaloric properties of DyMn2Si2 compound with multiple magnetic phase transition

Abstract Structural, magnetic and magnetocaloric properties of the ternary intermetallic compound DyMn 2 Si 2 are studied by X-ray diffraction and magnetization measurements. It is found that DyMn 2 Si 2 crystalizes with tetragonal ThCr 2 S 2 -type structure and exhibits four successive magnetic transitions at low temperature, around 20 K, 31 K, 38 K and 82 K, named respectively as T 1 , T 2 , T 3 and T 4 transitions. Large values of magnetic field (>35 kOe) favor antiferromagnetic clusters and give rise to exchange bias effect. The different responses of T 2 and T 3 to field change, induces two non-identical isothermal entropy change (-ΔS M ) peaks. The maximum values of -ΔS M occur in temperatures around T 3 and reaches 8.2 J/kgK, for a magnetic field change of 50 kOe. Also, the presence of transitions T 2 and T 3 close to each other induces a table-like magnetocaloric effect (MCE) in a wide temperature range. Thus, the peculiar magnetic properties observed for DyMn 2 Si 2 compound are interesting for low temperature magnetic refrigeration.