Experimental Study on Metamagnetism in Ce₅Si₃

Abstract

We have measured specific heat in magnetic fields, magnetization at ambient and high pressures and magnetostriction of Ce₅Si₃ and its alloy system (Ce_1-xLa_x)₅Si₃. As temperature is lowered, the systems for x < x_c ∼ 0.15 undergo successive phase transitions, while those for x > x_c exhibit only a spin-glass transition. From the obtained experimental results, we have constructed phase diagrams, magnetic field versus temperature for Ce₅Si₃ and temperature versus La-concentration for (Ce_1-xLa_x)₅Si₃. The measurements of the magnetization have revealed that the metamagnetism occurs for field directions of H || a as well as H || c. We discuss an origin of the metamagnetism on the basis of a crystalline electric field model and thermodynamic analysis.