Grating‐Based Eight‐Channel Lan‐WDM Silicon Photonic Transceiver for Tb/s Applications

Abstract

An eight‐channel local‐area‐network wavelength division multiplexing silicon photonic transceiver is designed within a 5 mm × 5 mm chip area. This integrated chip is composed of a set of perfectly vertical grating couplers, interleaved angled‐MMI wavelength division (de)multiplexers, silicon E‐O modulators, and germanium waveguide photodetectors. The multiplexer exhibits an IL of (4.5–5.8) dB and average crosstalk ≈−20 dB. Due to the limited bandwidth of the 2‐D GC, the IL of the demultiplexer is 5.17 dB at minimum, with a channel nonuniformity of 5.53 dB. The EO modulator and germanium waveguide PD exhibit 3‐dB bandwidths of 45 and 47 GHz, respectively. With a customized fiber array packaged, a back‐to‐back data transmission capacity of 1.56 and 1.42 Tb/s with BERs below the SD‐FEC limit is demonstrated for the transmitter and receiver, respectively. By connecting the transmitter and receiver, the dynamic performance of the transceiver chip is characterized, and the total data capacity of eight wavelength channels is 1.18 Tb/s. To show the advantage of transmission distance, 2 and 10 km SMF transmission experiments are also carried out. Through close integration with matched electronic circuits, the data capacity of this transceiver chip can be potentially boomed to 1.6 Tb/s.