Metal-insulator transition and resistive switching in Y-doped CeO2 ceramics

Y-doped ceria, Y0.16Ce0.84O1.92, is an oxide ion conductor that shows n-type conductivity under a small applied voltage. With increasing voltage, resistive switching by 2–3 orders of magnitude occurs that is reversible with some hysteresis and is enhanced in atmospheres of reduced pO2. The switching is a bulk effect, is not associated with Schottky barriers or with a crystallographic transition, occurs rapidly after a premonitory onset period depending on conditions and shows characteristics of a Mott transition. This is the third known example of low field-induced resistive switching in a bulk ceramic and represents an emergent phenomenon in materials that are taken outside their zone of thermodynamic stability.