Origin of direct current drift in electro-optic polymer modulator

Abstract

Characteristics of the dc drift phenomenon in electro-optic polymer modulators have been analyzed. It is found that the dc drift originates from the difference between the dielectric relaxation times of the guiding and cladding layers. The dc drift is accelerated as the intensity of the guided light increases. Furthermore, it becomes faster when the device is exposed to visible light. The effect of the guided light and visible light on the dc drift is interpreted in terms of the photoconductivity of the guiding layer.

Wide-bandwidth lasers and modulators for RF photonics

“…Polymer layers have finite conductivity, which effect electrical response under dc and ac applied biases. This effect was studied using an equivalent-network approach [65], [100], [101]. Every layer of the optical waveguide can be modeled as a parallel RC circuit.…”

Planar polymeric multilayer structures for electro-optical applications

“…Finally, the third layer was grown on the top of the structure with the same conditions. We tested also the compatibility of the structures with gold electrodes, one between substrate and layer 1 and one at the top of the structure above layer 3, with the aim to apply directly an aligning electric field between the two electrodes [7,8]. Gold electrodes of 250 nm thickness were deposited using a sputter machine Emnitech model K550X.…”

High speed electro-optic polymer phase modulator using an in-plane slotline RF waveguide

“…One can use GaAs or Si wafers as a substrate material for the microstrip structure because the substrate loss is small compared to CPW structure. For the CPW structure, large RF coupling to the substrate results in high substrate loss 8 . We have tested RF transmission loss from two silicon wafers having different resistivity, 10 Ω⋅cm and 10 4 Ω⋅cm, as a substrate to verify how much the RF energy escapes into the substrate.…”