Showing papers by "Giovanni Pierattini published in 1993"
ARCO1
TL;DR: In this paper, the propagation of a TE laser beam in a waveguide-nematic liquid crystal planar stack is studied as a function of an externally applied magnetic field, and the power losses depending on the molecular reorientation in the liquid crystal layer have been both theoretically computed and experimentally measured.
7 citations
ARCO1
TL;DR: The transition from the transmission to the reflection regime for an Ar+-laser beam propagating in the new polymeric blend PMMA-EVA at a nonlinear interface has been observed in this paper.
Abstract: The transition from the transmission to the reflection regime for an Ar+-laser beam propagating in the new polymeric blend PMMA-EVA at a nonlinear interface has been observed. A comparison between the experimental data and a calculation of the input optical intensity at which this transition should occur (1.45×107 W m−2) is presented using Kaplan's theory. The results suggest the presence of thermally induced optical bistability in PMMA-EVA.
3 citations
ARCO1
TL;DR: Reflected field intensity distributions for surface plasmon wave excitation in an attenuated total internal reflection configuration for different metal film thickness are reported in this paper, where measured lateral shift is compared with theoretical predictions.
3 citations
ARCO1
TL;DR: In this article, a heterodyne type Mach-Zehnder detection interferometer is described, which permits concurrent measurements of the thermooptic coefficients of quartz retardation plates in the thermal range 25 −265°C.
1 citations
TL;DR: In this article, a heterodyne detection interferometer is described that can be efficiently used to control the state of polarization (SOP) and the phaseshift induced by polarizing optical devices.
Abstract: A heterodyne detection interferometer is described that can be efficiently used to control the state of polarization (SOP) and the phaseshift induced by polarizing optical devices. The basic equations are derived. The technique is used to measure the SOP of linear retarders.
23 Jul 1993
TL;DR: In this paper, a tensor operator formalism based approach to the light-induced anisotropy (LIA) effects in initially isotropic media subjected to a biharmonic laser field (pump-probe) is presented.
Abstract: A general approach to the light-induced anisotropy (LIA) effects in initially isotropic media subjected to a biharmonic laser field (pump-probe), that is based on a tensor operator formalism, is presented. Using such a theoretical treatment, we propose novel nonlinear spectroscopic techniques. We show new results dealing with advantageous measurement of the 3rd-order nondegenerate nonlinear susceptibility (3NNS), including the 3NNS phase (3NNSP) and the real and imaginary parts of the effective 3NNS. Figure 1 is the schematic illustration of a method for measuring 3NNSP in the framework of optically heterodyned polarization spectroscopy (OHPS) when the components of 3NNS are connected by the Kleinman relationships. In the standard OHPS arrangement with the slightly tilted analyzer and the linearly polarized probe beam at 45 to the major axis of the pump polarization ellipse, under tuning of the pump intensity W) or ellipticity (tans) we can find the minimum OHPS signal (AI which is determined by 3NNSP. Another possibility for measuring 3NNSP occurs when the linearly polarized pump and circularly polarized probe beams are used. In this case, the tangent of double azimuth of the output probe polarization is exactly equal to 3NNSP. The validity of the theoretical treatment presented is supported by the experimental data. Furthermore, we point out that some previous theoretical studies devoted to the similar problems are not quite correct and should be revised. In Fig. 2 the nonlinear polarization spectroscopy signal normalized to the maximum value is plotted as a function of c. The line 1 is fitted with experimental data for malachite green in water.1 The experimental results for crystal violet, methylene-blue and rhodamine-B in aqueous solutions are shown by circles, triangles and squares, respectively. They are in rather good agreement with our experimental curve 2.