Resistivity and Hall effect of the magnetic ternary compoundUNi2Si2

Electrical-resistivity and Hall-effect measurements on single-crystal ${\mathrm{UNi}}_2$ ${\mathrm{Si}}_2$ have been performed between 4.2 and 300 K. The resistivity ρ is highly anisotropic, with a larger magnitude parallel to the c axis. Above 150 K, dρ/dT is small and positive in the ab plane and negative along the c axis. Distinct features and anomalies have been observed in both the resistivity and the Hall-effect measurements. They are associated with the magnetic phase-transition temperatures at 123, 103, and 53 K observed by neutron-diffraction and scattering experiments.