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Optically transparent Eu3+-doped Pb(Mg1/3Nb2/3)O3–0.25PbTiO3 (PMN–0.25PT:Eu3+) relaxor ferroelectric ceramics with high piezoelectricity were prepared by oxygen-atmosphere sintering followed by hot-press sintering.

Relaxor ferroelectric 0.75(Pb 1-3x/2 La x)(Mg 1/3 Nb 2/3)O 3-0.25(Pb 1-3x/2 La x)TiO 3 (La 3+ :PMN-PT x/75/25, where x = 2.8, 3.0, 3.5, and 4.0 mol% of La 3+) transparent ceramics were fabricated by the combination of oxygen atmosphere pressureless sintering and hot-pressing sintering process. The optical transmittances of above four ceramics are higher than 60% at the wavelength of 500-900 nm. La 3+ :PMN-PT 3.0/75/25 exhibits the highest transparency around 70% at 900 nm which is very close to the theoretical transmittance 71%. Each of the four ceramics exhibits the pure perovskite phases. They show fully dense microstructures and their relative densities are higher than 99.8%. The ferroelectric and dielectric measurements indicate that these four ceramics exhibit relaxation characteristics. With increasing La 3+ content, (200) peak in XRD patterns shifts to higher angles and the average grain size increases, while the temperature T max corresponding to the maximum r , the remanent polarizations P r and coercive fields E c decrease gradually.

We derive an analytical expression for the propagation factor (known as M 2 -factor) of electromagnetic concentric rings Schell-model (EM CRSM) beams in non-Kolmogorov turbulence by utilizing the extended Huygens-Fresnel diffraction integral formula and the second-order moments of the Wigner distribution function (WDF). Our results show that the EM CRSM beam has advantage over the scalar CRSM beam for reducing the turbulence-induced degradation under suitable conditions. The EM CRSM beam with multi-rings far-fields in free space is less affected by the turbulence than the one with dark-hollow far-fields or the electromagnetic Gaussian Schell-model (EGSM) beam. The dependence of the M 2 -factor on the beam parameters and the turbulence are investigated in detail.