![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
The dielectric constant (ϵ) and the specific heat (C p ) of Bi-layered perovskite SrBi 2 Ta 2 O 9 (SBT) are discussed in comparison with ferroelectric thin films of BaTiO 3 . SBT shows very weak and broad temperature dependence with 100 K temperature width. The peak value of ϵ is only 300 at T c, which is two orders as small as that of typical perovskite-type ferroelectrics. Although these perovskites exhibit quite different nature, the dielectric behavior of BaTiO 3 thin film is similar to those in SBT. The dielectric and structural analogy between SrBi 2 Ta 2 O 9 and thin film suggests that this bulk layered ferroelectric is a good example of ultra-thin ferroelectric model with 2 monolayers of TaO 6 perovskite units, free from any misfit lattice strain with substrate and surface charge at the interface with electrodes.