Random magnetic anisotropy in a new compound $\mbox{Sm}_2\mbox{Ag}\mbox{Si}_3$

Abstract

We report the experimental study on the structural and magnetic properties of a new ternary intermetallic compound $\mathrm{S}{\mathrm{m}}_2\mathrm{AgS}{\mathrm{i}}_3$. The properties of the sample were investigated in detail by X-ray diffraction, dc-magnetization, and heat capacity measurements. The polycrystalline compound of $\mathrm{S}{\mathrm{m}}_2\mathrm{AgS}{\mathrm{i}}_3$ crystallizes in the $\mathrm{ThS}{\mathrm{i}}_2$-type tetragonal structure (space group $I_{4_1}/amd$). The temperature-dependent dc-magnetization and heat capacity results demonstrate that the compound undergoes ferromagnetic behaviour with a Curie temperature ($T_C$) of 14 K. The large coercive field in hysteresis loops and the thermomagnetic irreversibility in the ferromagnetic region revealed that the compound exhibits a large magnetic anisotropy. The magnitude of the applied field and the coercivity obtained from the M-H loops corroborate with the thermomagnetic irreversibility in the magnetization data. The magnetic contribution of the heat capacity reveals a broad Schottky-type anomaly above $T_C$, due to the presence of the crystal electric field effect of $\mathrm{S}{\mathrm{m}}^{3+}$ in $\mathrm{S}{\mathrm{m}}_2\mathrm{AgS}{\mathrm{i}}_3$.