Ultra-High-Speed Deeply Etched Electrooptic Polymer Modulator With Profiled Cross Section

Abstract

In this paper, we present a novel ultra-high-speed polymer based electrooptic modulator that features a profiled, deeply etched cross section. We show that by profiling the side walls of the modulator and varying the thickness of the dielectric stack that broadband operation can be achieved whilst maintaining a very low drive voltage in a compact device. Initially a quasi-TEM analysis is undertaken in order to determine the modulators response to topographical variation followed by a full-wave analysis on the optimized device. The full-wave analysis is employed in order to determine any frequency dispersion effects with respect to the modulators characteristic impedance <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Zc</i> , microwave effective index <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Nm</i> , microwave and dielectric losses alpha <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</i> and alpha <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</i> , and the half-wave voltage-length product <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pi</sub> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</i> .