Ring resonator-based on-chip modulation transformer for high-performance phase-modulated microwave photonic links

Area of Science:

• Photonics
• Integrated Optics
• Microwave Photonics

Background:

• Phase-modulated microwave photonic links (PM-MPLs) offer advantages like bias-free operation.
• Converting phase modulation to intensity modulation is crucial for many applications.
• Existing methods often suffer from laser phase noise conversion.

Purpose of the Study:

• To propose and demonstrate a novel wideband on-chip photonic modulation transformer.
• To achieve efficient phase-to-intensity (or vice versa) modulation conversion with minimal phase noise.
• To integrate this transformer into a photonic integrated circuit (PIC) for advanced signal processing.

Main Methods:

• Utilizing waveguide-based ring resonators for device construction.
• Designing a PIC with two modulation transformers and a notch filter in TriPleX™ waveguide technology.
• Employing a 2x2 splitting circuit and three continuously tunable ring resonators.

Main Results:

• The device performs phase-to-intensity modulation transform and carrier suppression simultaneously.
• A single-fiber-span PM-MPL with a 12 GHz RF bandwidth was demonstrated.
• The spurious-free dynamic range performance is comparable to Class-AB MPLs.

Conclusions:

• The proposed photonic modulation transformer is a key building block for on-chip microwave photonic signal processors.
• This technology enables high-performance, compact, and reconfigurable PM-MPLs.
• The device offers a viable solution for low-noise modulation conversion in photonic integrated circuits.