Compact electro-optic modulator on lithium niobate

Fast electro-optic modulators with an ultracompact footprint and low power consumption are always highly desired for optical interconnects. Here we propose and demonstrate a high-performance lithium niobate electro-optic modulator based on a new 2 x 2 Fabry-Perot cavity. In this structure, the input and reflected beams are separated by introducing asymmetric multimode-waveguide gratings, enabling TE0 - TE1 mode conversion. The measured results indicate that the fabricated modulator features a low excess loss of similar to 0.9 dB, a high extinction ratio of similar to 21 dB, a compact footprint of similar to 2120 mu m(2), and high modulation speeds of 40 Gbps OOK and 80 Gbps PAM4 signals. The demonstrated modulator is promising for high-speed data transmission and signal processing. (C) 2022 Chinese Laser Press