Optimal design of Birefringent Gires-Tournois optical interleaver

A new type BGTI, with only one GTI, can reduce PMD greatly and has much better temperature stability compared to traditional BGTI. The channel isolation rate of single-stage structure is not enough and result in crosstalk increasing and SNR reducing. To improve isolation rate, two cascaded BGTI are used to realize the second filter. Simulation and experiment results show that isolation rate is improved, the bandwidth is remained and PMD also reaches requirement design, successfully optimizing the system performance.