High-Q vertically-coupled microresonators built by wafer-bonding technique

Summary form only given. We demonstrate high Q vertically coupled passive microdisk resonators based on the InP material system as a first step towards utilizing active devices, and to understand the parameters limiting their performance. Vertical coupling is chosen because it exhibits two major advantages compared to the lateral geometry, namely: i) precise control of the coupling coefficient by epitaxial growth; ii) the material composition of the waveguides and resonator can be optimized and grown independently, which facilitates the design of active microdisk devices - ON/OFF switches, modulators and microdisk lasers.