Highly efficient phase-sensitive parametric gain in periodically poled LiNbO₃ ridge waveguide.

Area of Science:

• Nonlinear optics
• Integrated photonics
• Quantum optics

Background:

• Periodically poled lithium niobate (PPLN) waveguides are crucial for nonlinear optical processes.
• Optical parametric amplification (OPA) is a key technique for manipulating light properties.
• Phase-sensitive amplification (PSA) offers enhanced control over quantum states of light.

Purpose of the Study:

• To develop and experimentally demonstrate a PPLN ridge waveguide for phase-sensitive optical parametric amplification.
• To achieve high net phase-sensitive gain.
• To compare phase-sensitive gain with phase-insensitive gain in the developed device.

Main Methods:

• Fabrication of a periodically poled lithium niobate (PPLN) ridge waveguide.
• Experimental setup for cascaded second harmonic generation (SHG) and difference frequency generation (DFG).
• Measurement of phase-sensitive and phase-insensitive optical parametric gain.

Main Results:

• A highly efficient net phase-sensitive parametric gain of +18.6 dB was achieved.
• The phase-sensitive gain was +5.8 dB higher than the phase-insensitive gain.
• Successful confirmation of high-gain phase-sensitive amplification in the PPLN ridge waveguide.

Conclusions:

• The developed PPLN ridge waveguide enables efficient phase-sensitive optical parametric amplification.
• The device demonstrates superior performance for phase-sensitive gain compared to phase-insensitive gain.
• This work advances integrated photonic devices for quantum information processing and optical sensing.