Magnetocaloric properties of Nd₅Si_1.45Ge_2.55 compound under high hydrostatic pressure

Abstract

The magnetic and magnetocaloric properties of Nd₅Si_1.45Ge_2.55 compound has been studied under high hydrostatic pressure up to 0.9 GPa. At ambient pressure, the Curie temperature (T _C) and magnetocaloric effect (MCE) give values T _C=58.1 K and−Δ S _M=4.9 J/kg K. Both T _C and MCE weakly increase with pressure. Using the value of compressibility (1.7^*10⁻² GPa⁻¹), we showed that the values of dT _C/d V and d|−Δ S _M|/d V obtained from experiments under high pressure are sufficiently lower than those estimated from the x-dependence of the lattice cell volume of Nd₅(Si _x Ge_1−x )₄ compounds. It indicated that the changes of magnetocaloric properties cannot be explained only by volume effect.

Keywords:

• Magnetocaloric compounds
• Volume effect
• Magnetization
• Curie temperature
• Hydrostatic pressure

Acknowledgements

The financial support of the Grant Agency of the Czech Republic (Grant no. 106/06/0368) is acknowledged.