In Situ High-Pressure Correlated Transportation of Heavy Rare-Earth Perovskite Nickelates as Batch Synthesized within Eutectic Molten Salts at MPa-pO₂

The multiple magneto-/electrical quantum transitions discovered with d-band correlated metastable perovskite oxides, such as rare-earth nickelate (ReNiO3), enable applications in artificial intelligence and multifunctional sensors. Nevertheless, to date such investigation merely focuses on ReNiO3 with light or middle rare-earth composition, while the analogous explorations toward heavy rare-earth (ReHNiO3, ReH after Gd) are impeded by their ineffective material synthesis relying on GPa pressure. Herein, for the first time we synthesized the powder of ReHNiO3 in grams/batch with ∼1000 times lower pressure and ∼300 °C lower temperature in comparison to the previous ∼101 milligram/batch results, assisted by their eutectic precipitation and heterogeneous growth within alkali-metal halide molten salt at MPa oxygen pressures. Further in situ characterizations under high pressures within a diamond anvil cell reveal a distinguishing pressure predominated bad metal transport within the nonequilibrium state of ReHNiO3 showing high-pressure sensitivity up to 10 GPa, and the temperature dependences in electrical transportations are effectively frozen.