Optical phase cloning by an integrated dual-parallel Mach-Zehnder modulator

Area of Science:

• Photonics
• Laser Physics
• Optical Engineering

Background:

• Distributed-feedback (DFB) lasers exhibit wide frequency noise spectra.
• Traditional feedback loops for laser control have limitations in bandwidth and range.
• Accurate optical phase control is crucial for various photonic applications.

Purpose of the Study:

• To demonstrate a novel feed-forward method for optical phase cloning onto a DFB laser.
• To achieve high control bandwidth and wide capture/tuning range for laser frequency stabilization.
• To explore a hybrid integration approach for cost-effective photonic devices.

Main Methods:

• Utilizing a dual-parallel Mach-Zehnder modulator in a feed-forward configuration.
• Cloning the optical phase of a master oscillator onto a DFB slave laser.
• Characterizing the residual phase error, control bandwidth, and capture/tuning range.

Main Results:

• Achieved a residual phase error of 113 mrad.
• Demonstrated a control bandwidth of hundreds of megahertz.
• Obtained a gigahertz-level capture and tuning range.

Conclusions:

• The feed-forward Mach-Zehnder modulator approach effectively clones optical phase onto DFB lasers.
• This method significantly outperforms conventional feedback loops.
• The technique is suitable for hybrid integration into compact, cost-effective devices.