Low-driving-voltage band-operation LiNbO3 modulator with lightwave reflection and double-stub structure

A reflection-type Mach-Zehnder LiNbO3 optical modulator with a double-stub structure that can modulate both forward and backward lightwave to achieve low-driving-voltage optical modulation for band-operation is developed. Using optical reflection the modulation efficiency is doubled. The halfwave-voltage of the fabricated modulator was 2.9 V at 7 GHz.