Heterogeneous integration of a high-speed photodiode with microcavity solitons for on-chip mmWave generation

We present a photonically driven on-chip millimeter wave (mmWave) source enabled by the heterogeneous integration of a high-speed InGaAs/InP photodiode and silicon nitride (Si 3 N 4 ) microcavity solitons. The chip delivers mmWaves with −18dBm of electrical power at a frequency of 98 GHz with kHz-class linewidth and low phase noise and marks a significant advancement in on-chip photonic mmWave source performance. This breakthrough not only demonstrates capabilities of heterogeneous photonic integration but also offers a compact and scalable solution for future low-noise mmWave applications in communications and sensing technologies.