Easy-plane magnetocrystalline anisotropy in the multistep metamagnet CeIr3Si2

[摘要] The magnetization M(B), electrical resistivity rho, and specific heat measurements are reported on a single-crystalline sample of CeIr3Si2, whose structure is characterized with a zigzag chain of Ce ions along the orthorhombic a axis. This compound undergoes magnetic transitions at 3.9 and 3.1 K. Easy-plane magnetocrystalline anisotropy is manifested in the magnetization process. For B parallel to b and B parallel to c, M(B) curves have a ferromagnetic component of 0.2-0.3 mu(B)/Ce and show metamagnetic transitions in a field range from 0.7 to 1.3 T. At B=5 T, M(B parallel to b) and M(B parallel to c) are 11 times larger than M(B parallel to a). Electrical resistivity is also anisotropic, rho(b)congruent to rho(c)>= 2 rho(a). The magnetic part of rho exhibits a double-peak structure with maxima at 15 and 350 K. The analysis of M(B) and paramagnetic susceptibility using a crystal-field model revealed unusually large energy splitting of 500 and 1600 K for the two excited doublets, respectively. The overall splitting is comparable to the largest value ever reported for Ce compounds, 2000 K in the unusual ferromagnet CeRh3B2 with a closely related structure.

[发布日期] 2007-11-01

[关键词] MAGNETIC-PROPERTIES;CERH3B2;CERIUM;BEHAVIOR