Mode-selective switch on silica-based PLC platform

Optical mode switch is a crucial component for the mode-division multiplexing (MDM) system. In this paper, we demonstrate a thermo-optical (TO) mode-selective switch on silica-based planar lightwave circuit (PLC) platform. The 2 × 1 thermo-optical (TO) mode-selective switch based on Mach–Zehnder interferometer consists of an adiabatic coupler and a symmetric Y-branch. The input optical mode E00 (E10) is converted to E10 (E00) mode while the light is coupled from different input ports by changing the working state of heater. With 2% index-contrast, a compact mode switch on silica-based PLC platform is fabricated. According to experimental results, the fabricated mode-selective switch shows an insertion loss lower than 5 dB and a mode extinction ratio higher than 24 dB for two modes at 1550 nm. The crosstalk is lower than −10.54 dB from 1500 nm to 1600 nm. The power consumption for two modes are 433.24 mW and 440.15 mW, respectively. The rise time and fall time of the switch are 560.9μs and 794.8μs.