No abstract

The authors report on hybrid electro-optic (EO) polymer–sol-gel modulators with low half-wave voltage (Vπ) and low insertion loss. Larger EO coefficient r33 results from the high poling field achieved when EO polymer is sandwiched between sol-gel cladding layers. The reduced interelectrode distance (d) resulting from the elimination of the sol-gel core layer in the active region further reduces Vπ. Straight channel phase modulators operate with Vπ=4.2V at 1550nm using a reduced d of 11.5μm, which corresponds to an r33 of 78pm∕V, among the highest r33 reported. The authors also examine a Mach-Zehnder modulator with Vπ=3.9V using a conventional d of 15μm.

Ultraefficient poling of electro-optic polymers is reported using an organically modified sol-gel cladding layer. This poling technique has resulted in a Pockel’s coefficient enhancement of up to a factor of 2.5, going from 26pm∕V when poled without a sol-gel cladding to 65pm∕V when optimally poled with a sol-gel cladding. The poling process directly applies to a previously reported hybrid electro-optic polymer/sol-gel waveguide modulator and may have applications in other poled polymer based devices.