Large Magnetoresistance in PrNiO3 Thin Film Deposited by RF Magnetron Sputtering

Magnetic and magnetotransport properties of a similar to 12 nm PrNiO3 (PNO) thin film deposited on (001)-oriented LaAlO3 (LAO) substrate by RF magnetron sputtering are reported. An enlargement in the out-of-plane lattice constant of the film (a(FOP) = 0.389nm) as compared to that of the target (a(c) = 0.383nm) reflects the larger in-plane compressive strain in the film. The appearance of a hump-like feature in the high-resolution w - 2 theta scan indicates that the film may have defects like grain or twin boundaries. The film undergoes a transition from paramagnetic (PM) to antiferromagnetic (AFM) at T-N approximate to 150K. The pronounced divergence between the zero-field and field-cooled magnetization-temperature curves suggests a magnetically clustered state. At T << T-N , the magnetic moment is appreciably larger and resembles an AFM state. At T > T-N , the film shows a very weak semiconducting behavior, which is followed by a transition to an insulating state at T < T-N . A magnetic field-induced metallic state is seen just below T-N and is associated with large thermal hysand teresis. The film also exhibits a negative magnetoresistance which is much larger than reported earlier in nickelates. The observed anomalous behavior could be due to the magnetic field-induced destabilization of the AFM state and spin fluctuations.

Automated summary

The magnetic and magnetotransport properties of a PrNiO3 thin film deposited on a LAO substrate are investigated. The film shows an enlargement in the out-of-plane lattice constant, indicating larger in-plane compressive strain and the presence of defects. The film undergoes a transition from paramagnetic to antiferromagnetic state at around 150K. It also exhibits a weak semiconducting behavior at high temperatures and a negative magnetoresistance, which is attributed to the destabilization of the antiferromagnetic state.