To improve the orientational stability of the chromophore induced by an electric field in a second-order nonlinear optical polymer, we have synthesized a thermally stable and cross-linkable azo dye, 4-[(4‘‘-aminophenyl)sulfonyl]-4‘-[N,N-bis(2-hydroxyethyl)amino]azobenzene. The transparent films with silica as matrix and organic chromophore as cross-linking agent were then prepared by using a sol−gel process. The resulting films heated at 200 °C under a high-corona field exhibited the nonlinear optical coefficient d 33 = 32 pm/V in Maker-fringe measurement. Long-term stability of second-harmonic coefficients in these films was observed even at 160 °C.

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We have made x-ray diffraction and etching studies of Cd1−xMnxTe samples with x≥0.05, and optical transmission studies when x≥0.45. We found that samples with x=0.05 and x=0.57 were zinc-blende-structured monocrystals, but that those with x=0.20 and 0.35 lacked four-fold symmetry and were heavily twinned. Those with 0.45 and 0.65 showed 6-mm symmetry which is most likely due to multiple twinning, but could be due to the presence of hexagonal crystallites with a c/a ratio of (6)1/2.

PLZT 9/65/35 single crystals were irradiated with 1.5 MeV krypton ions at 25–450°C in the HVEM-Tandem Facility at Argonne National Laboratory. In-situ TEM was performed during irradiation in order to determine the critical amorphization dose. At room temperature, the material was completely amorphized after a dose of only 1.9×1014 ions/cm2, less than one fifth of the critical amorphization dose for silicon (1×1015 ions/cm2). The critical amorphization dose for the PLZT material increased with increasing irradiation temperature. At 450°C, amorphization was not observed after a dose of 1.1×10 15ions/cm2.

The transit times of 10-MHz longitudinal and transverse ultrasonic waves have been measured between 1.5 and 298 K for ceramic PbZr03 and PbMgl/3Nbp/303 The elastic stiffness moduli deduced therefrom have normal temperature dependences in PbZr03. However, in PbMgl/3Nb2/303 the moduli have a broad minimum in the region of the diffuse ferroelectric transition, a very slight dip near 90 K, and an anomalous temperature dependence below 90 K. The latter features may indicate the presence of a phase transition which has not been reported previously. For PbZr03 the elastic Debye temperature 8&"' at 1.5 K is 396+4 K. This value is within experimental error of a recent calorimetric value. For PbMgl/3Nb2/303 SD ' --38228 K, which is much larger than the calorimetric value, indicating that in PbMgl/3Nb2/303 acoustic lattice vibrations cannot account for all of the "Debye" term in the specific heat. It is suggested that anomalies in the specific heat may be due to weak bonding between Pb ions and the Mg06 or Nb06 octahedra and to strains in the samples.