Title :
Frequency-dependent propagation characteristics of coplanar waveguide electrode on 100GHz Ti:LiNbO3 optical modulator
Author :
Noguchi, Keisuke ; Miyazawa, H. ; Mitomi, O.
Author_Institution :
NTT Opto-Electron. Labs., Kanagawa
fDate :
4/2/1998 12:00:00 AM
Abstract :
The microwave propagation characteristics of a coplanar waveguide electrode in the frequency range 45 MHz-110 GHz were studied in order to evaluate the factors which limit the performance of a high-speed ridged Ti:LiNbO3 optical modulator. Since the effective microwave index is constant in the higher frequency range, neither structure nor material dispersions of the modulator are observed. In addition to the conductor loss, the dielectric loss also increases above 20 GHz. The dielectric loss is shown to originate not only in the LiNbO3 substrate, but also in the silicon oxide buffer layer
Keywords :
coplanar waveguides; dielectric losses; lithium compounds; optical modulation; optical planar waveguides; optical waveguide components; ridge waveguides; titanium; 45 MHz to 110 GHz; LiNbO3:Ti; buffer layer; conductor loss; coplanar waveguide electrode; dielectric loss; effective microwave index; frequency-dependent propagation characteristics; microwave propagation characteristics; ridged optical modulator;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19980284
