Fig. 1. Schematic of 1×8 optical switch architecture based on tree structure

Fig. 2. Schematic of the structure of 1×2 MZI

Fig. 3. Transmission spectra of different paths, the insets show the electric field distribution of MMI. (a) Transmission spectra of paths 1-2 and 1-3 of 1×2 MMI; (b) transmission spectra of paths 1-3 and 1-4 of 2×2 MMI

Fig. 4. Simulation results of phase variation with input power,the insets show the cross section of thermally shifted phase arm and thermal field simulation results, respectively

Fig. 5. Physical diagrams of optical switch after electrical and optical encapsulation. (a) Gold wire bonding diagram of optical switch chip; (b) packaged optical switch; (c) PCB diagram; (d) substrate structure; (e) physical diagram of optical switch

Fig. 6. External driver for optical switch chip. (a) Physical multi-channel voltage source; (b) connection plate

Fig. 7. Optical switch calibration test system

Fig. 8. Spectra of eight transmission paths and test waveguide for optical switch. (a) Test waveguide; (b) I₁-O₁; (c) I₁-O₂; (d) I₁-O₃; (e) I₁-O₄; (f) I₁-O₅; (g) I₁-O₆; (h) I₁-O₇; (i) I₁-O₈

Fig. 9. Transmission spectra for power maximization at target output port of optical switch. (a) I₁-O₁; (b) I₁-O₂; (c) I₁-O₃; (d) I₁-O₄; (e) I₁-O₅; (f) I₁-O₆; (g) I₁-O₇; (h) I₁-O₈

Fig. 10. Response time test system of 1×8 TO switch

Fig. 11. Test results of response time of optical switch. (a) 100 Hz; (b) 1 kHz; (c) 5 kHz; (d) 10 kHz