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Presents experimental studies on primary and secondary pyroelectric effects in lead zirconate titanate, lead titanate and zinc oxide thin films. Details of experimental techniques used; Characteristics of pyroelectric materials; Examination of the performance of the thin films as infrared radiation detectors.

Presents a study which deposited crack-free transparent ferroelectric lanthanum-doped lead zirconate titanate (PLZT) thin films on silicon substrates using the sol-gel deposition technique. Method and materials used in preparing silicon wafer samples; Approach used in the wet chemical etching of the samples; Observation on the wave guiding properties of the PLZT.

The components of the third-order nonlinear optical susceptibility χ(3) for the 1002-cm-1 mode of neat benzenethiol have been measured using coherent anti-Stokes Raman scattering with continuous-wave diode pump and Stokes lasers at 785.0 and 852.0 nm, respectively. Values of 2.8 ± 0.3 × 10-12, 2.0 ± 0.2 × 10-12, and 0.8 ± 0.1 × 10-12 cm·g-1·s2 were measured for the xxxx, xxyy, and xyyx components of |3χ(3)|, respectively. We have calculated these quantities using a microscopic model, reproducing the same qualitative trend. The Raman cross-section σRS for the 1002-cm-1 mode of neat benzenethiol has been determined to be 3.1 ± 0.6 × 10-29 cm2 per molecule. The polarization of the anti-Stokes Raman scattering was found to be parallel to that of the pump laser, which implies negligible depolarization. The Raman linewidth (full-width at half-maximum) Γ was determined to be 2.4 ± 0.3 cm-1 using normal Stokes Raman scattering. The measured values of σRS and Γ yield a value of 2.1 ± 0.4 × 10-12 cm·g-1·s2 for the resonant component of 3χ(3). A value of 1.9 ± 0.9 × 10-12 cm·g-1·s2 has been deduced for the nonresonant component of 3χ(3). Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The components of the third-order nonlinear optical susceptibility \(\chi^{(3)}\) for the \(1002-cm^{–1}\) mode of neat benzenethiol have been measured using coherent anti-Stokes Raman scattering with continuous-wave diode pump and Stokes lasers at 785.0 and 852.0 nm, respectively. Values of \(2.8 ± 0.3 × 10^{–12}\), \(2.0 ± 0.2 × 10^{–12}\), and \(0.8 ± 0.1 × 10^{–12} cm g^{–1} s^2\) were measured for the xxxx, xxyy, and xyyx components of \(|3\chi^{(3)}|\), respectively. We have calculated these quantities using a microscopic model, reproducing the same qualitative trend. The Raman cross-section \(\sigma_{RS}\) for the \(1002-cm^{–1}\) mode of neat benzenethiol has been determined to be \(3.1 ± 0.6 × 10^{–29} cm^2\) per molecule. The polarization of the anti-Stokes Raman scattering was found to be parallel to that of the pump laser, which implies negligible depolarization. The Raman linewidth (full-width at half-maximum) \(\Gamma\) was determined to be \(2.4 ± 0.3 cm^{–1}\) using normal Stokes Raman scattering. The measured values of \(\sigma_{RS}\) and \(\Gamma\) yield a value of \(2.1 ± 0.4 × 10^{–12} cm g^{–1} s^2\) for the resonant component of \(3χ^{(3)}\). A value of \(1.9 ± 0.9 × 10^{–12} cm g^{–1} s^2\) has been deduced for the nonresonant component of \(3\chi^{(3)}\)., Chemistry and Chemical Biology

The absolute Raman cross section \(\sigma_{RS}\)of the first-order \(1332-cm^{−1}\) optical phonons in type Ia natural diamond was measured using 785- and 1064-nm pump lasers for the excitation of Raman scattering. A small temperature-controlled blackbody was used for the signal calibration of the 785- and 1064-nm Raman systems. Measurements were made with a 0.9-mm thick (111) natural diamond sample. Values of \(2.7\pm0.6×10^{−29}\) and \(0.95\pm0.2×10^{−29} cm^2\) per carbon atom were determined for \(\sigma_{RS}\) for 785- and 1064-nm excitation, respectively. The corresponding values of the Raman scattering efficiency S are \(3.8\pm0.8×10^{−7}\) and \(1.3\pm0.3×10^{−7} cm^{−1} sr^{−1}\). The values of the Raman polarizability |d| for 785-, and 1064-nm excitation are \(6.8\pm0.7×10^{−16}\) and \(8.1\pm0.8×10^{−16} cm^2\), respectively. Our measured values of |d| are larger than the previously measured values of \(4.4\pm0.3×10^{−16}\) and \(4.6\pm0.7×10^{−16} cm^2\) using 514.5- and 694-nm excitation, respectively. |d| vs. excitation photon energy was computed for the range from 1.0 eV (1240 nm) to 4.0 eV (310 nm) using time-dependent density functional theory. The computed values of \(5.8×10^{−16}\) and \(5.3×10^{−16} cm^2\) for 514.4- and 694-nm excitation, respectively, are larger than the corresponding measured values of |d|. The computed values of \(5.2×10^{−16}\), and \(5.0×10^{−16} cm^2\) for 785- and 1064-nm excitation are smaller than the corresponding values of |d| measured in this work. The computed value of |d| in the static limit is \(4.7×10^{−16} cm^2\). Modification of |d| due to IaA and IaB defects, computed for a 64-atom supercell, is less than 5%., Chemistry and Chemical Biology

The absolute Raman cross section \(\sigma_{RS}\) of the first-order \(519 cm^{−1}\) optical phonon in silicon was measured using a small temperature-controlled blackbody for the signal calibration of the Raman system. Measurements were made with a 25-mil thick (001) silicon sample located in the focal plane of a 20-mm effective focal length (EFL) lens using 785-, 1064-, and 1535-nm CW pump lasers for the excitation of Raman scattering. The pump beam was polarized along the [100] axis of the silicon sample. Values of \(1.0±0.2×10^{−27}\), \(3.6±0.7×10^{−28}\), and \(1.1±0.2×10^{−29} cm^2\) were determined for \(\sigma_{RS}\) for 785-, 1064-, and 1535-nm excitation, respectively. The corresponding values of the Raman scattering efficiency S are \(4.0±0.8×10^{−6}\), \(1.4±0.3×10^{−6}\), and \(4.4±0.8×10^{−8} cm^{−1} sr^{−1}\).The values of the Raman polarizability |d| for 785-, 1064-, and 1535-nm excitation are \(4.4±0.4×10^{−15}\), \(5.1±0.5×10^{−15}\), and \(1.9±0.2×10^{−15} cm^2\), respectively. The values of \(4.4±0.4×10^{−15}\) and \(5.1±0.5×10^{−15} cm^2\) for |d| for 785- and 1064-nm excitation, respectively, are 1.3 and 2.0 times larger than the values of \(3.5×10^{−15}\) and \(2.5×10^{−15} cm^2\) calculated by Wendel. The Raman polarizability |d| computed using the density functional theory in the long-wavelength limit is consistent with the general trend of the measured data and Wendel’s model., Chemistry and Chemical Biology, Physics