Tunable Photonic Molecules for Spectral Engineering in Dense Photonic Integration

• Published in: Future Trends in Microelectronics pp. 337 - 348
• Main Authors: Souza, M. C. M. M, Rezende, G. F. M, Zuben, A. A. G, Wiederhecker, G. S, Frateschi, N. C, Barea, L. A. M
• Format: Book Chapter
• Language: English
• Published: Hoboken, NJ, USA Wiley 2016; John Wiley & Sons, Inc
• Edition: 1
• Subjects: coupled microring resonators; extinction ratio; flexible spectral response; free spectral range; photonic circuitry; photonic‐based solutions; spectral engineering; standard tuning techniques; Optical filters; Optical device fabrication; Optical resonators; Optical coupling; Resonators; Optical waveguides; Photonics
• ISBN: 1119069114; 9781119069119
• DOI: 10.1002/9781119069225.ch3-7

This chapter presents some recent advances in realizing novel devices with flexible spectral response using systems of coupled microring resonators, or photonic molecules. The design flexibility of such devices offers extra degrees of freedom to perform spectral engineering using standard tuning techniques, such as microheaters and pn junctions. The successful deployment of photonic‐based solutions across different fields depends on the ability to fully control the spectral response of the building blocks of photonic circuitry. The basic functionalities required for most applications are now available in a variety of designs and platforms but the challenge remains to realize these functionalities with devices allowing for flexible and reconfigurable spectral control. A microring resonator for instance, while presenting a certain level of design freedom and spectral tunability, has its filtering and power enhancement properties dictated by its free spectral range (FSR), linewidth, and extinction ratio (ER), which are difficult to control actively.