F.S. Tan

Microresonators As Building Blocks For VLSI Photonics

In the last years much effort has been taken to arrive at optical integrated circuits with high complexity and advanced functionality. For this aim high index contrast structures are employed resulting in photonic wires in conventional index guiding waveguides or in photonic bandgap structures. In both cases the number of functional elements within a given chip area can be enhanced by several orders of magnitude: VLSI photonics. In this talk optical microresonators are presented as promising basic building blocks for filtering, amplification, modulation, switching and sensing. Active functions can be obtained by monolithic integration or a hybrid approach using materials with thermo‐, electro‐ and opto‐optic properties and materials with optical gain. Examples are mainly taken from work at MESA+.

Design and characterization of waveguide-coupled cylindrical microring resonators in Si/sub 3/N/sub 4/

Cylindrical micro-resonators have been proposed as all-optical switch, micro-laser, add-drop filters and they open the route to large area reduction complex integrated optics devices. They have been studied in literature both theoretically and experimentally. In this paper we present preliminary results of microring resonators in Si/sub 3/N/sub 4/ technology. The experimental free spectral ranges and finesses of the ring modes are compared with detailed simulations.

High finesse vertically coupled waveguide-microring resonators based on Si/sub 3/N/sub 4/-SiO/sub 2/ technology

A simple waveguiding structure with vertically coupled microring resonators has been realized. A finesse of more than 100 could be achieved by using Si/sub 3/N/sub 4/-SiO/sub 2/ technology. The devices have been realized by means of standard optical lithography processes and reactive ion etching (RIE).

ULTRA-COMPACT SPECTRAL SLICER DEVICES BASED ON MICRORING RESONATORS

In Wavelength Division Multiplexing (WDM), access network spectral slicer devices in connection with a broadband light source are attracting low-cost alternatives for the laser diodes that are required for transmission in the desired wavelength channels. The proposed ultra-compact spectral slicer devices consist of microring resonators with slightly different radius and consequently slightly different resonant wavelength. Single and cascaded multiple microring devices have been fabricated and characterized to demonstrate the desired functionality. Cascaded devices show better performance in term of lower crosstalk, higher rejection ratio and faster roll-off. Moreover, they open the possibility to improve the spectral efficiency of the individual channels without introducing additional channel crosstalk.

Minimized losses in a cylindrical microresonator by use of a cladding: experimental and numerical study

We present an experimental study of the influence of a cladding on the losses in a Si/sub 3/N/sub 4/ on SiO/sub 2/ cylindrical microresonator (MR). The experimental results are corroborated with detailed numerical simulations and examples of devices which exploit the presence of a cladding are given.