Fig. 1. Semiconductor laser with high power and low noise. (a)-(c) are the semiconductor laser made by Emcore^[18] in the U.S.A., Apic^[19] in the U.S.A. and Z.K. Litecore^[20] in China, respectively

Fig. 2. Electro-optic modulator with broad bandwidth and low half-wave voltage. (a) Traditional lithium niobate modulator^[22]; (b) Thin-film lithium niobate modulator^[23]; (c) Plasmonic modulator^{[14, 21]}; (d) InP and silicon modulator with high linearity^[24-26]

Fig. 3. Photodetector with high saturation power. (a) Product of photodetector by II-VI Incorporated^[27]; (b) Chip of InP photodetector^[28]; (c) Chip of InP on SOI photodetector^[29]; (d) Chip of Ge on SOI photodetector^[30]

Fig. 4. Beamformer chips based on path selection to switch different delays. (a) Silicon nitride 5-bit delay chip with 4 channels^[31]; (b) Silicon dioxide 5.5-bit delay chip with 8 channels^[32]; (c) Silicon 5-bit beam control chip with 8 channels^[33]

Fig. 5. Beamformer chips based on dispersion tuning of microring resonators. (a) Silicon nitride multi-wavelength tunable delay chip^[34]; (b) Silicon nitride tunable delay chip with 4 channels^[35]; (c) Silicon beam control chip with 4 channels^[36]

Fig. 6. Integrated microwave photonic filters. (a) Microwave photonic filter based on silicon nitride microring resonator^[37]; (b) Microwave photonic filter based on SBS effect^[38]; (c) Microwave photonic filter based on cascaded silicon nitride microring resonators^[39]; (d) SOI integrated microwave photonic filter^[40]; (e) Monolithically integrated InP microwave photonic filter^[41]

Fig. 7. Integrated microwave photonic signal generation chips. (a) InP monolithically integrated microwave photonic oscillator chip^[42]; (b) SOI integrated microwave photonic oscillator chip^[43]; (c) SOI integrated arbitrary microwave waveform generation chip^[44]; (d) SOI integrated chip for the generation of linearly chirped microwave signals^[45]

Fig. 8. Integrated microwave photonic frequency conversion chips. (a) InP monolithically integrated microwave photonic frequency conversion chip^[46]; (b) SOI integrated microwave photonic frequency conversion chip^[47]

Fig. 9. Silicon photonics analog to digital conversion chip^[48]

Fig. 10. Programmable microwave photonic signal processing chips. (a) Programmable microwave photonic integrated signal processing chip based on tunable MZI units^[52]； (b) Programmable microwave photonic integrated signal processing chip based on tunable microdisks^[53]