Nd 0.8 Y 0.2 NiO 3 thin films with room-temperature metal–insulator transition deposited by pulsed laser ablation

A solid solution between neodymium and yttrium nickelates has been stabilized that displays a room-temperature metal–insulator transition and lattice parameters predicted by Vegard’s law. Nd0.8Y0.2NiO3 thin films were grown on (110) NdGaO3 by pulsed laser deposition, and structural investigations were carried out by x-ray diffraction and transmission electron microscopy, which revealed the presence of domains with the c axis either parallel or perpendicular to the substrate plane. The growth conditions leading to a metal–insulator transition at room temperature (311 K) were defined. The strain effect induced by the substrate was explained, and a critical film thickness close to 100 nm was established.