Simultaneous optical digital half-subtraction and -addition using SOAs and a PPLN waveguide.

Area of Science:

• Optical computing
• Integrated photonics
• Digital signal processing

Background:

• Optical data processing offers high speed and bandwidth.
• Simultaneous arithmetic operations are crucial for advanced optical computing architectures.
• Existing methods often require complex setups or lack integration.

Purpose of the Study:

• To demonstrate a novel optical module for simultaneous half-subtraction and half-addition.
• To achieve high-speed (5 Gbit/s) bit-wise operations using optical components.
• To integrate key functions into a compact and efficient module.

Main Methods:

• Utilizing cross-gain modulation (XGM) in semiconductor optical amplifiers (SOAs) for generating Difference/Sum (XOR) and Borrow outputs.
• Employing difference-frequency-generation (DFG)-based wavelength conversion in a periodically poled lithium niobate (PPLN) waveguide for the Carry output.
• Combining optical signals using a passive optical coupler.

Main Results:

• Successful demonstration of a simultaneous optical half-subtracter and half-adder module.
• Generation of Borrow (/X*Y) and Difference/Sum (X XOR Y) outputs via XGM in parallel SOAs.
• Generation of Carry (X*Y) output using DFG in a PPLN waveguide.
• Achieved 5 Gbit/s data stream processing with a maximum power penalty of 1.0 dB.

Conclusions:

• The developed optical module efficiently performs simultaneous half-subtraction and half-addition.
• The integration of XGM in SOAs and DFG in PPLN waveguides enables high-speed optical arithmetic.
• This work contributes to the advancement of all-optical signal processing and computing systems.