Accession Number : ADP008080

Title :   Chalcogenide Glass Planar Waveguides: Z-Scan Investigation of Refractive Index Changes,

Corporate Author : ROME UNIV (ITALY)

Personal Author(s) : Bertolotti, M. ; Michelotti, F.

Report Date : APR 1992

Pagination or Media Count : 2

Abstract : Nonlinear properties of chalcogenide glasses (ChG) are very interesting both from the point of view of potential application in photonic devices ( as planar waveguides, fibers, coating films ) and new basic mechanisms in the field of short laser pulses. Recently the measurements of optical hysteresis in thin films of ChG were performed, showing the effect at light intensities lower thin those reported in the case of crystalline semiconductors. In the present work we have extended the measurements of nonlinear transmission of c.w. (Lambda=514.5 nm) and pulsed (Lambda=532 nm, Tau=70 ps ; 570 nm < Lambda < 630 nm, Tau=4 ps) laser excitation through thin films of ChG (As2Se3, AsSe, GeSe2, As2S3), which can act as planar waveguides. The z-scan technique was used to study the basic nonlinear properties of thin films ( thickness 0.2-2.0 micrometer). In this technique the transmission of a focussed laser beam, through a finite aperture in the far field, is measured as a function of the displacement (z) of the film along the propagation direction and about the focal plane.

Descriptors :   *CHALCOGENS, *LIGHT TRANSMISSION, *OPTICAL WAVEGUIDES, APERTURES, COATINGS, DISPLACEMENT, EXCITATION, FAR FIELD, FIBERS, FOCAL PLANES, FUNCTIONS, HYSTERESIS, INTENSITY, LASER BEAMS, LIGHT, MEASUREMENT, PHOTONICS, SEMICONDUCTORS, THICKNESS, THIN FILMS, USSR, SELENIDES, LIGHT PULSES.

Subject Categories : Electrooptical and Optoelectronic Devices
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE