Temperature Dependence of Electrical Resistivity in Ferromagnetic GdNi Single Crystal

Abstract

The temperature dependence of the electrical resistivity of GdNi single crystal has been investigated in the temperature range 4.2–300 K. The Curie temperature T_c was 72±1 K. The resistivity was proportional to T² below T_c with large coefficients 6.1×10⁻⁹ Ω·cm·K⁻² for a-axis and 5.4×10⁻⁸ Ω·cm·K⁻² for b-axis. The resistivity ρ_mag due to magnetic disorder for b-axis was about ten times larger than for a- and c-axes. This anisotropy was interpreted as the difference of the effective mass of conduction electrons. The magnetic exchange interaction J_eff was estimated as 0.07 eV on the basis of the localized magnetic model.