High-Speed Waveguide-coupled Photodiode Arrays on Thin-film Lithium Niobate Platform

The study presents a demonstration of InP/InGaAs modified uni-traveling carrier (MUTC) photodiode (PD) arrays heterogeneously integrated on the thin-film lithium niobate platform. To divide the input optical power evenly, a 1×N multimode interferometer (MMI) is employed to feed the PDs through N waveguides. The PD arrays, consisting of 2, 3, and 4 PDs, exhibit 3-dB bandwidths of 82 GHz, 67 GHz, and 62 GHz, respectively. The measured output power of the 1 ×4 PD array reaches -2.3 dBm at 30 GHz.