Mid-infrared silicon photonic phase shifter based on microelectromechanical systems

Mid-infrared (MIR) photonic integrated circuits have gen-erated considerable interest, owing to their potential appli-cations, such as thermal imaging and biochemical sensing. A challenging area in the field is the development of reconfigurable approaches for the enhancement of on-chip functions, where a phase shifter plays an important role. Here, we demonstrate a MIR microelectromechanical sys-tem (MEMS) phase shifter by utilizing an asymmetric slot waveguide with subwavelength grating (SWG) claddings. The MEMS-enabled device can be easily integrated into a fully suspended waveguide with SWG cladding, built on a silicon-on-insulator (SOI) platform. Through engineering of the SWG design, the device achieves a maximum phase shift of 6 pi, with an insertion loss of 4 dB and a half-wave -voltage-length product (V pi L pi) of 2.6 Vmiddotcm. Moreover, the time response of the device is measured as 13 mu s (rise time) and 5 mu s (fall time).(c) 2022 Optica Publishing Group