Abstract

We propose a newly designed X-cut lithium niobate (LiNbO3) optical modulator. It has a two-step back-slot structure to satisfy the velocity-matching condition without the buffer layer of silicon dioxide (SiO2). Accordingly,this modulator can achieve low drive voltage and low optical insertion loss. In addition, the dc-drift phenomena due to the buffer layer can be suppressed. This structure is fabricated with micromachining technology using excimer laser ablation. The optical 3-dB bandwidth of the fabricated modulator reaches 30 GHz, and the drive voltage is less than 3 V at 1 kHz. From the measurement of the optical eye diagram at 43.5-Gb/s, clear eye openings were obtained. This modulator is sufficient for 40-Gb/s optical transmission systems.

[IEEE ]

Activation Energy for Dc-drift in X-cut LiNbO₃ Optical Intensity Modulators

Naoki Mitsugi, Kazumasa Kiuchi, and Hirotoshi Nagata
Appl. Opt. 37(34) 8147-8146 (1998)

Very low voltage single drive domain inverted LiNbO₃ integrated electro-optic modulator

F. Lucchi, D. Janner, M. Belmonte, S. Balsamo, M. Villa, S. Giurgola, P. Vergani, and V. Pruneri
Opt. Express 15(17) 10739-10743 (2007)

Air-gap structure between integrated LiNbO₃ optical modulators and micromachined Si substrates

Ryo Takigawa, Eiji Higurashi, Tadatomo Suga, and Tetsuya Kawanishi
Opt. Express 19(17) 15739-15749 (2011)

Effects of parasitic modes in high-speed LiNbO₃ optical modulators

Woo Kyung Kim, Woo-Seok Yang, and Han-Young Lee
Opt. Express 12(12) 2568-2573 (2004)

Lifetime Estimation for Hermetically Packaged 10 Gb/sec LiNbO₃ Optical Modulators

Hirtoshi Nagata, Naoki Mitsugi, Kazumasa Kiuchi, and Junichiro Minowa
Appl. Opt. 35(34) 6842-6843 (1996)