Abilio Almeida; Yonny Romaguera; Daniel Alfredo Mota; Alex Tkach; Javier Cruz; Joaquim A. Moreira
Among the family of transition metal oxides, the MTaO3 (M=Li, Na, K) compounds have attracted a great interest from researchers from a fundamental and technological point of view. LiTaO3 is isomorph to LiNbO3 and both exhibit ferroelectricity at room temperature. Owing to the polar characteristics, these materials can be used in transducers, sensors, and optical applications. Contrarily, NaTaO3 and KTaO3, though possessing polar soft modes, do not exhibit
ferroelectricity at finite temperatures. All these materials possess a highly polarizable lattice, yielding their properties very sensitive to defects, impurities, elastic, and applied electric fields. These factors can easily induce ferroelectricity and intermediate glass- or relaxor-like states. Though a relative high number of works has been published in bulk MTaO3 systems, their study in thin film form is still scarce and their behaviour is yet not fully understood. In this work MTaO3 thin films were prepared by radio frequency...