Low-loss and high-Q Ta(2)O(5) based micro-ring resonator with inverse taper structure

Area of Science:

• Materials Science
• Optical Engineering
• Nanotechnology

Background:

• Tantalum pentoxide (Ta2O5) is a promising material for optical applications due to its high refractive index and low optical loss.
• Micro-ring resonators are key components in photonic integrated circuits for wavelength filtering and signal processing.
• Achieving high quality factors (Q) and low loss in Ta2O5-based devices is crucial for enhanced performance.

Purpose of the Study:

• To fabricate and characterize a low-loss, high-Q Ta2O5-based micro-ring resonator.
• To investigate the optical properties of Ta2O5 thin films for guided wave devices.
• To assess the potential of Ta2O5 for novel applications in photonic integrated circuits.

Main Methods:

• Fabrication of Ta2O5 micro-ring resonators and channel waveguides using reactive sputtering and post-annealing.
• Optical characterization of the micro-ring resonator, including coupling efficiency and loss coefficient extraction.
• Measurement of propagation and coupling losses in Ta2O5 channel waveguides using the cut-back method.

Main Results:

• A Ta2O5 micro-ring resonator with a diameter of 200 μm was successfully fabricated.
• An unloaded Q factor exceeding 44,000 and a loss coefficient of 8.1 dB/cm were achieved for the micro-ring resonator.
• The Ta2O5 channel waveguide exhibited a propagation loss of 1.5 dB/cm and a coupling loss of 3.2 dB.

Conclusions:

• The developed Ta2O5 micro-ring resonator demonstrates excellent optical performance, with a high Q factor and low loss.
• The fabrication process and material properties of Ta2O5 are suitable for creating high-performance guided wave devices.
• This Ta2O5 technology presents a viable alternative for advanced photonic integrated circuits and potential new applications.