Introduction to Integrated Optical Modulators

Integrated optical modulators consist of active and passive planar optical waveguides designed and fabricated on semiconductor-based integrated photonics platforms. This chapter provides a general overview of integrated optical modulators. In the first part, optical modulators are classified into three types with respect to optical-waveguide layout. The optical waveguides are treated schematically as building blocks. Their structures and theoretical characteristics are described in detail in Chapter 4. This chapter focuses on the MZ optical modulator because of its versatility in the high-quality generation of optical data in intensity modulation and phase modulation in principle. Integrated MZ optical modulators on a silicon-photonics platform are highlighted in the last part of this chapter as the theme of this book.