Investigation on an ultra-compact 1×2 polymer electro-optic switch using cross-coupling 2N + 1 vertical-turning serial-coupled microrings

摘要

Generic model and thorough investigation are proposed for a novel 1×2 polymer electro-optic (EO) switch based on one-group 2N +1 vertical-turning serial-coupled microrings. For realizing boxlike flat spectrum as well as low crosstalk and insertion loss, resonance order and coupling gaps are optimized. The MRR switches with N ≥ 1 reveal favorable box-like spectrum as when compared with the simple device with only one microring (N = 0). For obtaining ＜-30 dB crosstalk under through-state, the dependency of switching voltage on N is determined as 7.19 × exp(-N/0.72) +1.72 (V). Under the operation voltages of 0 V (drop state) and the predicted switching voltages (through state), the device performances are analyzed, and 1 ≤ N ≤ 10 is required for dropping the insertion loss (drop state) below 10dB. The crosstalk of the ten devices (N = 1 - 10) are ＜ -19.5dB under drop state and ＜ -28.7 dB under through state, and the insertion losses of the devices (N = 1 - 10) are ＜ 9.715 dB under drop state and ＜ 1.573 dB under through state. The device also has ultra-compact footprint size of only 0.33-1.06 mm, which is only 1/10-1/3 of those of our previously reported polymer EO switches based on directional coupler or Mach-Zehnder interferometer structures. Therefore, the proposed device is capable of highly integration onto optical networks-on-chip.