Tunable coupling regimes of silicon microdisk resonators using MEMS actuators

Area of Science:

• Photonics
• Integrated Optics
• Microelectromechanical Systems (MEMS)

Background:

• Silicon microdisk resonators are key components in photonic integrated circuits.
• Controlling coupling regimes is crucial for device functionality.
• Existing methods for tuning coupling are often complex or limited.

Purpose of the Study:

• To demonstrate tunable coupling regimes in silicon microdisk resonators using MEMS actuation.
• To dynamically control the interaction between a waveguide and a microdisk.
• To enable reconfigurable photonic integrated circuits.

Main Methods:

• Integration of silicon waveguides, microdisks, and MEMS actuators on a silicon-on-insulator (SOI) substrate.
• Utilizing MEMS actuation to precisely vary the gap spacing between the waveguide and the microdisk.
• Characterization of waveguide transmittance and microdisk quality factor across different coupling regimes.

Main Results:

• Demonstration of under-, critical-, and over-coupling regimes through MEMS actuation.
• Achieved 30 dB transmittance suppression in the critical coupling regime.
• Measured a high quality factor (Q) of up to 10^5 for the microdisk.
• Tuned group delay from 27 ps to 65 ps.
• Tuned group velocity dispersion from 185 ps/nm to 1200 ps/nm.

Conclusions:

• MEMS-actuated silicon microdisk resonators provide dynamic control over coupling regimes.
• This technology offers a compact and promising solution for reconfigurable photonic integrated circuits.
• The demonstrated tunability in delay and dispersion opens avenues for advanced optical signal processing.