Postprint version. Published in Fiber and Integrated Optics, Volume 16, Issue 3, January 1, 1997, pages 269-276. Copyright © 1997 Taylor & Francis. The definitive version is available online at: http://dx.doi.org/10.1080/01468039708221268.
NOTE: At the time of publication, the author Xiaomin Jin was not yet affiliated with Cal Poly.
Traveling wave Ti:LiNbO3 Mach-Zehnder optical modulators with buried electrodes and etched grooves in the SiO2 buffer layer are analyzed by the finite element method. The tradeoff between the bandwidth BW and the half-wave voltage Vπ is discussed. The value of BW/Vπ is used to weight the total performance of the modulator. Taking a thick buffer layer and etching deep grooves in the buffer layer are demonstrated as two effective methods to improve the performance of the modulator. A 3-dB optical bandwidth of 18 GHz with half-wave voltage 5V at a wavelength of 1.55 pm could be obtained even though the electrode is not very thick. When the requirement of half-wave voltage is not very critical, a bandwidth of more than 100 GHz can be obtained.
Electrical and Computer Engineering