Open AccessSecond‐Order Optical Response in Electrically Polarized Sodo‐Niobate Amorphous Thin Films: Particularity of Multilayer Systems
Author(s) -
Karam Lara,
Adamietz Frédéric,
Michau Dominique,
Murugan Ganapathy Senthil,
Cardinal Thierry,
Fargin Evelyne,
Rodriguez Vincent,
Richardson Kathleen A.,
Dussauze Marc
Publication year - 2021
Publication title -
advanced photonics research
Language(s) - English
Resource type - Journals
ISSN - 2699-9293
DOI - 10.1002/adpr.202000171
Subject(s) - poling , lithium niobate , materials science , amorphous solid , second harmonic generation , thin film , optics , nonlinear optics , substrate (aquarium) , optoelectronics , crystal (programming language) , condensed matter physics , ferroelectricity , nanotechnology , physics , dielectric , chemistry , crystallography , laser , programming language , computer science , oceanography , geology
Herein, our attention is focused on the second‐order optical properties of thermally poled sodo‐niobate amorphous thin films through an original methodology that combines both macroscopic and microscopic second harmonic generation techniques. By probing the geometry and the magnitude of the second‐order nonlinear (SONL) optical response at different scales, a key aspect of thin film's poling mechanisms compared with bulk glasses is demonstrated that lies in the appearance of a charge accumulation at the film/substrate interface and that is described by the Maxwell–Wagner effect. A way to minimize this effect is then proven by promoting an induced built‐in static field in the plane of the film using a microstructured electrode. A SONL optical susceptibility as high as 29 pm V −1 is measured and its geometry and location are controlled at the micrometer scale; it constitutes an improvement of at least one order of magnitude compared with other poled amorphous inorganic materials and is comparable with that of lithium niobate single crystal.