Electronic structure and ferroelectricity in SrBi2Ta2O9

The electronic structure of SrBi2Ta2O9 is investigated from first-principles, within the local density approximation, using the full-potential linearized augmented plane wave (LAPW) method. The results show that, besides the large Ta(5d)-O(2p) hybridization which is a common feature of the ferroelectric perovskites, there is an important hybridization between bismuth and oxygen states. The underlying static potential for the ferroelectric distortion and the primary source for ferroelectricity is investigated by a lattice-dynamics study using the Frozen Phonon approach.Comment: 17 pages, 7 figures. Phys. Rev. B, in pres

Structure and morphology of epitaxial PbZrO3 films grown by metalorganic chemical vapor deposition

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Familial transitional cell carcinoma among the population of Iceland

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Local probing of the polarization state in thin Pb(ZrTi)O-3 films during polarization reversal

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Optical properties of PbTiO3, PbZrxTi1−xO3, and PbZrO3 films deposited by metalorganic chemical vapor on SrTiO3

Epitaxial PbZrxTi1−xO3 (PZT) films have been prepared by metalorganic chemical vapor deposition on SrTiO3 substrates. Two sets of films of thicknesses 50–100 and 700–1400 nm, containing 0%, 40%, 60%, and 100% Zr, were prepared and investigated. The refractive index n was determined by ellipsometry for the thin films and by reflectivity for the thicker films. Results were obtained over the energy range from 1.55 to 3.72 eV, and with a Cauchy-fit extrapolation down to 0.62 eV. The refractive-index curves show a systematic variation with composition. For all compositions, n is close to 3.2 at 3.72 eV (333 nm), while at 1.55 eV (800 nm) n is 2.35 for PZ (x=1) and 2.61 for PT (x=0). In agreement with previous results we find that the optical band gap is essentially independent of composition for PZT. We obtained 3.6±0.1 eV. The n(E) results were analyzed by a Wemple–DiDomenico dispersion analysis, yielding results for the dispersion region in the ultraviolet. Unlike the band gap, which is insensitive to composition in PZT, the dispersion energy Ed decreases from PT to PZ in the same fashion as the refractive index in the transparent region

Damage after annealing and aging at room temperature of platinized silicon substrates

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Nonlinear optical and electrostatic force microscopy for ferroelectric polarization imaging

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Incorporation of Pb, Ti, and Zr into MOCVD grown PbZrxTi1-xO3 thin films

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