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Characterization of Anisotropic Leaky Mode Modulators for Holovideo
Published on: March 19, 2016
Small-signal system-level analysis of traveling-wave Mach-Zehnder modulators
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Mach-Zehnder modulators are widely used in high-speed optical communication systems due to their versatility and their ability to adopt a traveling-wave design to reach high modulation bandwidths. Existing analytical descriptions of these devices have focused on the derivation of a normalized amplitude frequency response, but a more comprehensive, detailed analysis has thus far been lacking. In this paper, we use a rigorous mathematical framework to present a small-signal system-level analysis of traveling-wave Mach-Zehnder modulators. Special attention has been paid to the interaction between the electrical and the optical domains, and electro-optical-electrical (EOE) S-parameters are formally derived. From this, modulator gain and bandwidth are discussed in depth, as well as velocity matching, and the importance of the electrical phase and group index. Additionally, minimum transmission point biasing for coherent systems is analyzed and compared against quadrature point biasing.
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