7.3 HIGH-SPEED MODULATION
7.3.1 Basic Issues, Principles, and Limitations
The speed of the modulation of light is limited by several factors which may be
divided into two groups:
(1) limitations inherent to the modulator due to charging times, charge carrier
transit times, frequency-dependent loss, velocity mismatch of electrical and
optical fields in distributed structures, and so on
(2) limitations caused by interaction with the drive electronics due to mismatch
in impedances and interconnect parasitics.
The first group of limitations depends on the chosen modulator structure and will
be different for different types of modulators. For example, velocity mismatch of
electrical and optical fields may be an issue in relatively long distributed structure ...