Magnetic and Electronic Properties of Single Crystals of Perovskite Nickelate Oxide LaNiO3 Prepared by the Laser Diode Floating Zone Method

Using the laser diode floating zone method, single crystals of LaNiO3, a nickel oxide with perovskite structure, have been successfully prepared under a high oxygen pressure of 4 MPa (40 bar). Single crystal x-ray diffraction indicates that the crystal structure is rhombohedral with an Ni-O-Ni bond angle of 165.3(5)degrees. The resistivity rho below 30K obeys the Fermi liquid behavior, expressed as rho(T) = rho(0) + AT(2) (rho(0), A, and T being the residual resistivity, coefficient, and temperature, respectively) with rho(0) less than 10 mu Omega cm. The magnetic susceptibility is nearly independent of the temperature, though it shows a broad maximum around 200 K, which is similar to the results in recent studies using single crystals. In the Hall effect, the contribution of hole carriers to the electrical transport is manifested as a positive Hall coefficient. Analysis of the Hall resistivity using the two-carrier model has revealed that even though the majority carriers are electrons, the Hall coefficient is positive due to minority holes with a higher mobility. This study may shed a new light on the properties of a correlated metal, LaNiO3.