Single-mode, singly resonant, pulsed periodically poled lithium niobate optical parametric oscillator

Area of Science:

• Nonlinear optics
• Laser physics
• Materials science

Background:

• Optical parametric oscillators (OPOs) are crucial for generating tunable laser light.
• Achieving single longitudinal mode (SLM) operation in pulsed OPOs is challenging due to parasitic oscillations.
• Nd:YAG lasers are common pump sources in nonlinear optics.

Purpose of the Study:

• To demonstrate single longitudinal mode (SLM) operation in a pulsed periodically poled lithium niobate (PPLN) optical parametric oscillator (OPO).
• To suppress parasitic resonant oscillations in pulsed OPOs.
• To achieve narrow optical bandwidths for tunable laser generation.

Main Methods:

• Utilized a pulsed Nd:YAG laser to pump a periodically poled lithium niobate (PPLN) optical parametric oscillator (OPO).
• Incorporated a prism and an etalon for combined coarse and fine spectral resolution.
• Implemented a cavity design to eliminate parasitic oscillations of signal and idler waves.

Main Results:

• Achieved stable single longitudinal mode (SLM) operation.
• Obtained optical bandwidths below 300 MHz at signal wavelengths from 1.47 to 1.59 µm.
• Observed only a 9% reduction in pump depletion and negligible loss in extraction efficiency compared to broadband operation.

Conclusions:

• The combined prism-etalon spectral resolution effectively suppresses parasitic oscillations in pulsed OPOs.
• SLM operation is achievable in PPLN OPOs with minimal impact on efficiency.
• This technique provides a robust method for generating narrow-linewidth tunable laser sources.