Small Footprint and High-Speed X-Cut Thin LiNbO3 Sheet Optical Modulator with Folded Structure

Kenji AOKI  Jungo KONDO  Yuichi IWATA  Akira HAMAJIMA  Tetsuya EJIRI  Osamu MITOMI  Makoto MINAKATA 

Publication
C - Abstracts of IEICE TRANSACTIONS on Electronics (Japanese Edition)  Vol.J91-C  No.2  pp.166-172
Publication Date: 2008/02/01
Online ISSN: 1881-0217
Print ISSN: 1345-2827
Type of Manuscript: PAPER
Category: 
Keyword: 
X-cut LiNbO3,  optical modulator,  folded structure,  lightwave-microwave velocity matching, 

Full Text(in Japanese): PDF(715.8KB)

Summary: 
We discussed the effect of an optical and electrical length difference and electrode structure to the modulator bandwidth in a modulator with a folded structure. We demonstarted an X-cut thin LiNbO3 sheet optical modulator with a folded structure. Not only a high-speed, and low driving-voltage but also a small footprint size can be realized in the structure. A modulation bandwidth of 20 GHz and a low half-wave voltage of 2.0 V@dc, a low optical insertion loss of -4.9 dB and a small footprint chip size of 1.8 29 mm were obtained. We also propose a novel folded structure that the perfect velocity-matching can be achieved and modulation bandwidth expected to be wider.