Morphotropic phase transition studies in by far-infrared reflectance spectroscopy

Abstract

The morphotropic phase transition in the Pb(Zr x Ti 1−x )O 3 system has been studied by far-infrared reflectance spectroscopy. The reflectance measurements are performed on compositions with x = 0.0, 0.10, 0.20, 0.30, 0.35, 0.40 and 0.525 at room temperature in the frequency range 40-600 cm −1 . The spectrum is fitted with a model based on the factorized form of the dielectric function. The dependences of the mode frequencies, damping and oscillator strength on x are reported. The static dielectric constant is calculated from the frequencies obtained from the fitting. The observed experimental data show incomplete softening of the lowest E(1TO) mode towards the morphotropic phase boundary. The oscillator strength of the lowest mode carries nearly all the contribution to the lattice part of the dielectric constant.

Dynamical coupling inPb(Zr,Ti)O3solid solutions from first principles

“…Note also that the predicted frequency of the E mode is around 49 cm −1 at room temperature, which agrees rather well with the measured value of 60 cm −1 in Pb(Zr 0.55 Ti 0.45 )O 3 solid solution 25 . Figs.…”

Structural phase evolution of strontium-doped lead titanate thin films prepared by the soft chemical technique

“…The three triply degenerate T 1u modes are IR active, and so, the modes transform into 3A 1 + 3E irreducible representations. 22,23 Depending on the direction of propagation of the mode with respect to its polarization, the modes split into longitudinal optical (LO) and transversal optical (TO) components. The principal bands observed for pure PbTiO 3 (PST0), located in the regions of 686 and 765 cm −1 , correspond to the irreducible representations A 1 (3TO) and E(3LO), respectively, and may be assigned to the Ti−O bond stretching vibration.…”

Polar lattice vibrations and phase transition dynamics in Pb(Zr1–xTix)O3<

“…IR studies on PZT are scarcer. The first far IR reflectivity study on PZT was performed for the rhombohedral PZT 75/25 sample byŽelezný et al, 23 and room temperature reflectivity dependence on the composition was studied by Sivasubramanian et al 24 Transmission studies were done on thin films by Fedorov et al 25 and on ceramics by Araújo and colleagues, [26][27][28] but only above 400 cm −1 . Our group published several papers on IR properties of lanthanum-doped PZT (PLZT) 20,29,30 and doped soft and hard PZT, 21 but to understand the behavior of polar phonons, systematic IR studies on undoped PZT are more suitable.…”