Low-power integrated optical amplification through second-harmonic resonance

Area of Science:

• Photonics and Optical Engineering
• Quantum Information Science
• Materials Science

Background:

• Optical amplifiers are crucial for telecommunications, sensing, and quantum processing.
• Existing technologies like erbium-doped and semiconductor amplifiers have limitations in wavelength coverage, noise, and distortion.
• Optical parametric amplifiers (OPAs) offer broadband, quantum-limited amplification but require high power, hindering miniaturization.

Purpose of the Study:

• To demonstrate a miniaturized, low-power optical parametric amplifier (OPA) integrated on a thin-film lithium niobate platform.
• To overcome the high power requirements that have limited the practical deployment of OPAs.
• To achieve high gain and broadband amplification with significantly reduced input power for next-generation photonic applications.

Main Methods:

• Developed a second-harmonic-resonant integrated OPA design on thin-film lithium niobate.
• Utilized pump recirculation to enhance pump generation efficiency (95% conversion) and power utilization.
• Implemented a resonant architecture to effectively increase pump power and multiplex signal and pump without sacrificing bandwidth.

Main Results:

• Achieved >17 dB gain with <200 mW input power, an order of magnitude improvement over previous OPAs.
• Demonstrated flat, near-quantum-limited noise performance across an 110 nm bandwidth.
• The resonant design effectively increased the pump power by nearly an order of magnitude compared to single-pass designs.

Conclusions:

• The demonstrated low-power, integrated OPA on thin-film lithium niobate overcomes previous power limitations.
• This technology enables practical on-chip OPAs, paving the way for advancements in quantum and classical photonics.
• The resonant design offers efficient amplification with broadband, low-noise characteristics suitable for diverse photonic applications.