| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1536839 | Optics Communications | 2012 | 10 Pages |
By using two-section cosine-transitive coplanar waveguide grounded (CPWG) electrodes, a polymer directional coupler (DC) electro-optic (EO) switch is optimally designed with both relaxed fabrication tolerance under cross-state and high switching speed over 100 GHz. As a new theoretical view, based on Fourier transformation, a Fourier analysis technique and related formulas are presented with respect to the time- and frequency-domain responses under high-speed modulating and switching operations. Under 1550 nm, the bar- and cross-state voltages are 0 and 2.669 V, respectively, for the switch with a total length of 8378 μm. The insertion loss and crosstalk are less than 3.887 and − 30 dB, respectively. The 3-dB modulating bandwidth and cutoff switching frequency are about 110 and 131.6 GHz, respectively, and the 10–90% rise time and fall time are both about 3.80 ps. Owning to this configuration, its cutoff switching frequency is enhanced to 9 times of that of our previously reported EO switch with two-section separated reversed electrodes, which expands the ultra-high speed and large capacity applications for such switches. The proposed Fourier analysis method can also be adopted to evaluate the responses under the operation of any other form driving signals with Fourier transformation.
