Broadband optical frequency comb generation based on single electro-absorption modulation driven by radio frequency...

Area of Science:

• Photonics and Optical Engineering
• Nonlinear Optics
• Integrated Optics

Background:

• Broadband optical frequency combs (OFCs) are crucial for applications like spectroscopy and communications.
• Traditional OFC generation methods can be complex and expensive.
• Electro-absorption modulators (EAMs) offer a compact platform for optical signal generation.

Purpose of the Study:

• To propose and theoretically model a simple, low-cost method for generating broadband OFCs using a single EAM.
• To investigate the influence of radio frequency (RF) signal parameters on OFC characteristics.
• To analyze the performance of the generated OFC using optical system simulation software.

Main Methods:

• Generating a multi-frequency RF signal using an electrical power splitter and an arithmetic circuit.
• Driving a single electro-absorption modulator (EAM) with the synthesized multi-frequency RF signal.
• Developing a theoretical model for OFC generation and analyzing performance with OptiSystem software.

Main Results:

• The number of comb-lines in the OFC is directly proportional to the multiplication order of the RF source signal.
• The frequency spacing of the comb-lines is tunable and equals twice the RF source frequency.
• Increasing the EAM's chirp factor and modulation index enhances the number of comb-lines.

Conclusions:

• A simple and cost-effective broadband OFC generation scheme is demonstrated using a single EAM and a multi-frequency RF driver.
• The proposed method allows for tunable comb spacing and a high number of comb-lines.
• This approach offers a promising solution for practical OFC generation in various applications.