Pattern-effect-free all-optical wavelength conversion using a hydrogenated amorphous silicon waveguide with...

Area of Science:

• Photonics and Optical Communications
• Materials Science
• Semiconductor Devices

Background:

• Ultra-fast carrier decay is a recently discovered phenomenon in hydrogenated amorphous silicon (a-Si:H) waveguides.
• Optical Kerr nonlinearity in waveguides is crucial for all-optical signal processing.
• Pattern effects can degrade the performance of optical signal processing systems.

Purpose of the Study:

• To investigate the exploitation of ultra-fast carrier decay in a-Si:H waveguides for pattern-effect-free all-optical signal processing.
• To demonstrate the feasibility of using a 10 Gbit/s RZ-OOK data stream as a pump for degenerate four-wave mixing.
• To evaluate the performance of a-Si:H waveguides in terms of propagation loss and bit error rate (BER) characteristics.

Main Methods:

• Utilized a low-loss hydrogenated amorphous silicon waveguide with a propagation loss of 1.0±0.2 dB/cm at 1550 nm.
• Employed a 10 Gbit/s RZ-OOK (Return-to-Zero On-Off Keying) data stream as the pump source for degenerate four-wave mixing.
• Assessed BER performance using pseudo-random binary sequences (PRBS) of lengths 2(7)-1 and 2(31)-1.

Main Results:

• Demonstrated pattern-effect-free all-optical signal processing using the ultra-fast carrier decay in a-Si:H waveguides.
• Achieved degenerate four-wave mixing with a 10 Gbit/s RZ-OOK data stream.
• Observed no significant difference in BER characteristics between different PRBS lengths, indicating the absence of pattern effects.

Conclusions:

• Hydrogenated amorphous silicon waveguides are suitable for pattern-effect-free all-optical signal processing due to ultra-fast carrier decay.
• The technology shows promise for high-speed optical communication systems by mitigating pattern-dependent impairments.
• a-Si:H waveguides offer a viable alternative to crystalline silicon for advanced photonic applications.