An optically polished x-cut KTiOPO4 crystal of size 22×6×1.5mm3 was implanted with 2.8-MeV He ions to a dose of 1.5 × 1016 ions/cm2 at room temperature to form a waveguide. The prism coupling method was used to measure the modes and the fiber probe technique was used to measure the attenuation in the KTiOPO4 waveguide. The refractive index profile, nz, in the KTiOPO4 waveguide was given based on the procedure by Chandler and Lama [P.J. Chandler and F.L. Lama, Optica Acta 33, 123 (1986)]. The waveguide attenuation measured was 2.57 dB/cm for m = 1 mode. After annealing at 260 °C for 30 min, there was no obvious change in the KTiOPO4 waveguide attenuation.

We present a numerical method to find specific composite microstructures with targeted effective properties. The effective properties that may be prescribed are quite diverse and include transport, mechanical, and electromagnetic properties, as well as properties associated with coupled phenomena, such as piezoelectric and thermoelectric coefficients. We formulated the target problem as an optimization problem. To illustrate our general target optimization technique, we have successfully found two-phase composite microstructures having specified effective electrical or thermal conductivities at fixed volume fractions. The method can also be used to design microstructures with multifunctional characteristics.

The more-stringent requirements for densification of new out-of-equilibrium powders have created a growing demand for nonconventional rapid sintering processes. Among those, field-assisted sintering techniques (FASTs) have seen a recent renewed interest motivated by their ability to consolidate a large variety of powder materials into high densities in short times. Characterization of a range of FAST-consolidated materials displayed relevant associated surface effects, such as grain boundary cleaning with direct grain-to-grain contact and advanced densification without sintering aids. These effects may be attributed to phenomena ranging from dielectric breakdown to a possible nonconventional plasma generation. Such surface effects provided a better intergranular bonding of powder particles during subsequent sintering

The effects of low-energy electron bombardment during the chemical vapor deposition of diamond were studied. The film growth was monitored in real time with in situ phase-modulated ellipsometry, in order to trigger the electron bombardment at different growth stages. Ex situ Raman spectroscopy and scanning electron microscopy were employed to evaluate the crystalline quality and the morphology of the grown films, respectively. The results indicated that triggering the electron bombardment after high-quality scattered diamond crystallites had formed results in finely grained smoother films of similar diamond yield and crystalline quality as those grown without bombardment. However, the electron bombardment deteriorates the film crystalline quality and the diamond yield when it was triggered from the start of deposition.

Nanocrystalline yttria-stabilized zirconia (nc-Y-TZP) powders coated with 10 vol% sodium strontium silicate glass were prepared by the sol-gel method. The glass is found to uniformly coat the zirconia particles or particle aggregates. The presence of the glass was found to enhance the densification of the powder compacts leading to 97% of the theoretical density compared to 90% in the pure nc-Y-TZP. It also resulted in a fine microstructure, homogeneous particle shape, and narrow size distribution. The polyhedral-shaped faceted grains in the sintered pure Y-TZP were converted to round-shaped grains in the glass containing specimens

The orientation dependence of the ferroelectricity of epitaxially grown Bi4Ti3O12 thin films was investigated. The (001)-, (118)-, and (104)-oriented Bi4Ti3O12 films were epitaxially grown on (100)cCaRuO3//(100)SrTiO3, (110)cSrRuO3//(110)SrTiO3, and (111)cSrRuO3//(111)SrTiO3 substrates, respectively, by metalorganic chemical vapor deposition. Ferroelectric property with different magnitude was observed for (001)- and (118)-oriented films but for (104)-oriented film due to its large leakage current. The remanent polarization and the coercive field were 1.5 mC/cm2 and 15 kV/cm, 16.5 νC/cm2 and 132 kV/cm for the (001)- and (118)-oriented thin films, respectively. The spontaneous polarization (PS) was 4.0 νC/cm2 and 27.0 νC/cm2 for (001)- and (118)-oriented films, respectively. This was different from the result of SrBi2Ta2O9 in that the ferroelectricity was not observed for (001)-oriented one, and was in good agreement with the estimation from the crystal structure. The estimated PS values along the c and a axes of Bi4Ti3O12 were 4.0 and 48.4 νC/cm2, respectively, and agreed well with the reported values for the single crystal. Furthermore, both films showed good fatigue endurance after 7.8 × 1010 switching cycles measured with 500 kHz rectangular pulses.

The structure and composition of SiNx/Si/SiNx films were investigated by means of x-ray reflectivity, x-ray photoelectron spectroscopy, and atomic force microscopy. The three-layer films were prepared by radio-frequency magnetron sputtering under the condition of constant nitrogen flow and the argon flow. It was found that the deposition rate and surface structure of the silicon nitride films were mainly determined by the nitrogen flow rather than the argon flow. But the composition of the silicon nitride films was controlled by the gas flow ratio (FAr/FN2) used during sputtering.