Nonlinear properties of and nonlinear processing in hydrogenated amorphous silicon waveguides

Area of Science:

• Photonics and optical engineering
• Materials science for optical applications
• Nonlinear optics

Background:

• Nonlinear optical phenomena are crucial for advanced optical signal processing.
• Developing efficient materials for nonlinear optics in the telecommunication band is an ongoing challenge.
• Hydrogenated amorphous silicon nanowires present a novel material platform.

Purpose of the Study:

• To investigate hydrogenated amorphous silicon nanowires for nonlinear optics.
• To characterize their nonlinear optical properties in the telecommunication wavelength range.
• To assess their potential for high-speed optical data sampling.

Main Methods:

• Fabrication of hydrogenated amorphous silicon photonic nanowires.
• Extraction of the nonlinear parameter and figure of merit.
• Demonstration of four-wave mixing in a data sampling experiment.
• Investigation of material degradation and annealing recovery.

Main Results:

• A figure of merit greater than 2 was extracted for the nanowires.
• Nonlinear optical properties showed degradation over time, reversible by annealing.
• A four-wave mixing conversion efficiency of +12 dB was achieved.
• Successful demonstration of 320 Gbit/s serial optical waveform data sampling.

Conclusions:

• Hydrogenated amorphous silicon nanowires are a viable platform for telecommunication-wavelength nonlinear optics.
• The material exhibits good nonlinear performance, though stability requires attention.
• Annealing can restore the nonlinear optical properties, enhancing material robustness.