Design and analysis of high performance phase shifters on polymeric slot waveguides within liquid crystal cladding

Abstract

We present an on chip phase shifter based on a polymeric slot waveguide and a liquid–crystal cladding, which is capable of reaching high tuning ranges, low control voltages and low propagation losses. Our analysis includes a purely numerical 3D-Finite-Difference-Time-Domain method and a semi-analytical 2D-Finite-Element-Method approach. Both analyses are in agreement, and confirm the high performances. We have used an analytical method in order to study the values of the control voltages, and used electrostatic simulations to validate the approximations. Moreover, in addition to the slot waveguide, we show that it is possible to develop Y-Splitters with negligible values of insertion losses with the same technology, which enables this type of phase shifters to adapt to existing platforms of polymeric optical integrated circuits, significantly enhancing their modulation capabilities.