Flat-top interleavers using two Gires-Tournois etalons as phase-dispersive mirrors in a Michelson interferometer

We present our experimental investigations of a flat-top 50-GHz optical interleaver using two Gires-Tournois etalons (GTEs) as phase dispersive mirrors in a Michelson interferometer. The spectral characteristics of the interleaver in a 50-GHz channel spacing application exhibit a 0.5-dB passband larger than 43.8 GHz (88% of the spacing), a 25-dB stopband greater than 40 GHz (80% of the spacing), and a channel isolation higher than 30 dB. The result shows that the interleaver interferometer with novel GTE technique can simultaneously produce a 0.5-dB passband and a 25-dB stopband wider than other interferometer techniques.