Low-loss SiN 2×2 MMI 50/50 Couplers for Monolithically Integrated Silicon Photonics

We report two low-loss SiN 2×2 MMI 50/50 couplers for monolithically integrated silicon photonics. Both couplers achieve measured ILs of 0.07 dB at 1310 nm and below 0.25 dB over the O-band.