Compact, silicon-on-insulator, series-cascaded, contradirectional-coupling-based filters with 50 dB adjacent channel isolation

摘要

In this work, we present optical add/drop multiplexer (OADM) filters for coarse wavelength-division-multiplexing (CWDM) systems with high sidelobe suppressions that result in high adjacent channel isolations (A(i)). The filters are realized by using a compact, series-cascaded configuration of apodized, contradirectional-coupling-based filters. We experimentally demonstrate a device with a measured A(i) of 53 dB (these devices hold the promise of achieving even higher A(i)s). While having large A(i)s, our devices have the wide bandwidths and low insertion losses required for CWDM applications. In addition, our demonstrated OADM has a nearly constant group delay, which results in low dispersion in the passband. (C) 2019 Optical Society of America