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9. Electro-Optic Modulators

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9.1 Basic Operation Characteristics ofSwitches and Modulators

9.1.1 Modulation Depth (Modulation Index)

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9.1.2 Bandwidth

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9.1.3 Insertion Loss

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9.1.4 Power Consumption

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9.1.5 Isolation

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9.2 The Electro-Optic Effect

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9.3 Single-Waveguide Electro-Optic Modulators

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9.3.1 Phase Modulation

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9.3.2 Polarization Modulation

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9.3.3 Intensity Modulation

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9.3.4 Electro-Absorption Modulation

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9.4 Dual-Channel WaveguideElectro-Optic Modulators

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9.4.1 Theory of Operation

The Coupling Equations

Boundary Condition

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Solutions

where

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Optical Power

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9.4.2 Operating Characteristics ofDual-Channel Modulators

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9.5 Mach-Zehnder TypeElectro-Optic Modulators

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9.6 Electro-Optic ModulatorsEmploying Reflection or Diffraction

9.6.1 Bragg-Effect Electro-Optic Modulators

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9.6.2 Electro-Optic Reflection Modulators

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9.7 Comparison of Waveguide ModulatorsTo Bulk Electro-Optic Modulators

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9.8 Traveling Wave Electrode ConfigurationsFor high frequency operation, the dimension of the electrodeshould not be regarded as “lumped”

=

LCc

z effε1

z: characteristic impedance of a traveling wave electrode

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Electrodes with Coplanar Waveguide (CPW) structure