[OPTICAL REVIEW Vol. 18, No. 2 (2011) 203-211]
© 2011 The Japan Society of Applied Physics
Electro-Optic Modulation Analysis of a Y-cut Z-Propagation LiNbO3 Light Modulator: Comparison with an X-Cut Z-Propagation LiNbO3 Light Modulator and a Dual LiNbO3 Crystal Type Modulator
Kuniharu TAKIZAWA* and Lianhua JIN1
Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, Musashino, Tokyo 180-8633, Japan
1Department of Mechanical Systems Engineering, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu 400-8511, Japan
(Received October 14, 2010; Accepted February 9, 2011)
We analyzed dependence of modulation characteristics on manufacturing errors for a Y-cut Z-propagation (YZ) and an X-cut Z-propagation (XZ) LiNbO3 (LN) crystal light modulators. We investigated that the modulation of the YZ modulator is hardly affected by small rotation error of Z-axis, while the XZ modulator suffers significant influence. We also analyzed temperature characteristics of modulation of conventional temperature-compensation LN light modulator. These numerical results show that the modulated signal change of the YZ modulator due to temperature variance is not more than 2.5% of that of the temperature-compensation modulator, in the presence of applied electric field of integral times of the half-wave voltage, modulated signal of the YZ modulator is almost independent on the temperature.
Key words: LiNbO3 crystal, light modulator, electro-optic effect, birefringence, manufacturing error
*E-mail address: takizawa@st.seikei.ac.jp