Mid-infrared silicon photonic phase shifter based on microelectromechanical system

Area of Science:

• Photonics
• Integrated Optics
• Microelectromechanical Systems (MEMS)

Background:

• Mid-infrared (MIR) photonic integrated circuits are crucial for applications like thermal imaging and biochemical sensing.
• Reconfigurable on-chip functions are essential for advancing MIR integrated circuits.
• Phase shifters are key components for enabling reconfigurability in photonic circuits.

Purpose of the Study:

• To demonstrate a novel microelectromechanical system (MEMS) phase shifter for mid-infrared (MIR) applications.
• To utilize an asymmetric slot waveguide with subwavelength grating (SWG) claddings for enhanced phase shifting.
• To integrate a reconfigurable phase shifter onto a silicon-on-insulator (SOI) platform.

Main Methods:

• Fabrication of a fully suspended waveguide with SWG cladding on an SOI platform.
• Design and engineering of the SWG claddings to control phase shift.
• Integration of a microelectromechanical system (MEMS) for device actuation.
• Characterization of phase shift, insertion loss, and response time.

Main Results:

• Achieved a maximum phase shift of 6π.
• Demonstrated a low insertion loss of 4 dB.
• Obtained a half-wave-voltage-length product (VπLπ) of 2.6 V·cm.
• Measured fast response times: 13 µs (rise) and 5 µs (fall).

Conclusions:

• The developed MIR MEMS phase shifter offers significant reconfigurability for photonic integrated circuits.
• The use of SWG claddings provides an effective method for enhancing phase shifting capabilities.
• The device shows promise for advanced applications in thermal imaging and biochemical sensing.