Researchers demonstrate low-loss and polarization-independent integrated optical colorless ROADM

https://phys.org/news/2024-05-loss-polarization-independent-optical-colorless.html

"reconfigurable optical colorless add-drop multiplexer (ROADM), greater flexibility, compact, robust single-chip... balances dense integration, low insertion loss, polarization-independent... 32 inputs x 4 ports... high-index doped silica glass... 188 MZI-type switch elements... waveguides distributed across 2 vertical layers allowing waveguides to cross over each other, reducing crosstalk to <-50 dB for express channels, -40 dB for add/drop channels... optical neural networks, integrated quantum photonics"