A wavelength-selective add-drop switch using silicon microring resonator with a submicron-comb electrostatic actuator

Area of Science:

• Photonics
• Microelectromechanical Systems (MEMS)

Background:

• Silicon microring resonators are crucial for wavelength-selective optical switching.
• Tunable coupling mechanisms are needed to control light routing in microring resonators.

Purpose of the Study:

• To develop a wavelength-selective add-drop switch with a variable coupling mechanism.
• To integrate an electrostatic comb-drive microactuator with a silicon microring resonator for tunable optical coupling.

Main Methods:

• Fabrication of a suspended silicon microring resonator (500 nm wide, 260 nm thick, 63.4 microm long).
• Integration with an electrostatic comb-drive microactuator for adjustable air gap control.
• Characterization of optical transmittance under varying applied voltages (0V to 28.2V).

Main Results:

• Achieved a variable coupling mechanism by adjusting the air gap with the comb actuator.
• Demonstrated a 32.9 dB variation in transmittance from the input to the drop port.
• Observed a 7.83 dB decrease in through-port transmittance at 28.2V, with 55% intensity directed to the drop port.
• Measured a full-width-half-maximum bandwidth of 0.5 nm for the dropped light, yielding a Q-value of 3150.

Conclusions:

• The developed device functions as an effective wavelength-selective add-drop switch with tunable coupling.
• Electrostatic actuation provides precise control over optical coupling in silicon microring resonators.
• This technology holds promise for advanced optical communication and signal processing applications.