Fig. 1. Classification of integrated topological optoelectronic devices on-chip

Fig. 2. Cross-section scanning electron microscopy images of a one-dimensional microcavity composed of 20 layers of alternately titanium dioxide and silicon dioxide on both sides of the interface^[63]

Fig. 3. SEM image of an out of plane radiation topological laser based on BIC^[69]

Fig. 4. Topological power divider classification. (a) Schematic diagram of asymmetrically coupled power splitter based on coupling point displacement^[75]; (b) schematic diagram of asymmetric power divider based on asymmetric energy valley topology boundary^[76]; (c) SEM image of multi-channel coupled power splitter based on energy valley photonic crystal^[77]; (d) SEM image of wideband 50∶50 topological power divider^[78]

Fig. 5. Classification of topological wavelength multiplexers and filters on-chip. (a) Schematic diagram of a resonator composed of one-dimensional conjugated topological photonic crystals^[79]; (b) schematic diagram of topological demultiplexer on near-infrared film^[81]; (c) schematic diagram of THz on-chip topology demultiplexer^[82]; (d) SEM image of multi-channel coupled power splitter based on energy valley photonic crystal^[83]

Fig. 6. SEM image and experimental results of topological rainbow based on translation synthesis dimension^[86]

Fig. 7. Topology dimmer switch. (a) Schematic diagram of topological valley photonic crystal modulator realized by optically controlled refractive index modulation^[90]; (b) SEM image of energy valley router based on vortex selection^[91]; (c) SEM image of 1×2 topological thermo-optical switch based on topological phase shifter^[59]; (d) high speed and low power consumption of 2×2 thermo-optical switch based on dual-silicon topological nanobeam cavity^[92]

Fig. 8. Topological quantum device. (a) Two-photon quantum state topology protection based on waveguide array^[100]; (b) topologically protected energy valley photonic crystal quantum optical path^[103]