Strong Magnetocaloric Coupling in Oxyorthosilicate with Dense Gd Spins.

Searching for working refrigerant materials is the key element in the design of magnetic cooling devices. Herein, we report on the thermodynamic and magnetocaloric parameters of an phase oxyorthosilicate, GdSiO, by field-dependent static magnetization and specific heat measurements. An overall correlation strength of || ≈ 3.4 K is derived via the mean-field estimate, with antiferromagnetic correlations between the ferromagnetically coupled Gd-Gd layers. The magnetic entropy change -Δ is quite impressive, reaches 0.40 J K cm (58.5 J K kg) at = 2.7 K, with the largest adiabatic temperature change = 23.2 K for a field change of 8.9 T. At = 20 K, the lattice entropy is small enough compared to the magnetic entropy , / = 21.3, which warrants its potential in 2 -20 K cryocoolers with both the Stirling and Carnot cycles. Though with relatively large exchange interactions, the layered A-type spin arrangement ultimately enhances the magnetocaloric coupling, raising the possibilities of designing magnetic refrigerants with a high ratio of cooling capacity to volume.