Low-loss tantalum pentoxide photonics with a CMOS-compatible process

Abstract

We report a Ta 2 O 5 photonic platform with a propagation loss of 0.49 dB/cm at 1550 nm, of 0.86 dB/cm at 780 nm, and of 3.76 dB/cm at 2000 nm. The thermal bistability measurement is conducted in the entire C-band for the first time to reveal the absorption loss of Ta 2 O 5 waveguides, offering guidelines for further reduction of the waveguide loss. We also characterize the Ta 2 O 5 waveguide temperature response, which shows favorable thermal stability. The fabrication process temperature is below 350°C, which is friendly to integration with active optoelectronic components.