Highly Integrated Optical 4 $\,\times\,$4 Crossbar in Silicon-on-Insulator Technology

In this paper, we present the design, fabrication, and characterization of a highly integrated optical 4$\,\times\,$ 4 crossbar based on microring resonator add-drop filters. The designed crossbar structure, as small as $50\,\mu{\hbox {m}}\times50\,\mu{\hbox {m}}$, has been fabricated in CMOS compatible silicon on insulator technology. Finally, experimental results proving the proper operation of the fabricated crossbar structures are discussed.