Nanoseconds low-polarization-sensitivity wideband 1 × 2 photonic integrated wavelength selective switch on 3-μm silicon platform

As optical fiber communication systems evolve towards multi-band transmission (MBT) technology to maximize the fiber’s capacity, leveraging the entire low-loss window of optical fibers, there is a growing need for innovative optical components that can function outside the traditional C-band. Consequently, to route data channels through transparent MBT networks efficiently, the development of novel wavelength selective switches (WSSs) with wideband operation is crucial. Moreover, polarization-independent operation is essential to ensure stable and reliable signal transmission of data with random polarization changes across the network. In addition, photonic integration of the WSS allows for a compact and low cost volume solution. In this work, we demonstrate a wideband photonic integrated low polarization dependent 1 × 2 WSS with S-band to L-band operations and nanosecond switching speed based on a 3-μm silicon photonic platform. The design of the 1 × 2 WSS includes a 12-channel 100 GHz spaced polarization insensitive (PI) arrayed waveguide grating (AWG) as the demultiplexer/multiplexer (Demux/Mux) and 1 × 2 Mach–Zehnder interferometer (MZI) switch units with nanosecond switching speed. The experimental results demonstrate that from S-band to L-band, the device has the lowest on-chip insertion loss of 5.9 dB, the highest extinction ratio of 27.6 dB, the lowest polarization-dependent loss (PDL) of 0.1 dB, and a minimum of 36 mW/channel switching power consumption. Moreover, error-free operation at a 10−9 bit error rate (BER) was achieved with <1.2 dB power penalty at bit rates up to 30 Gbit/s NRZ-OOK and 25 Gbaud/s PAM4 data signals.