Synchronously pumped CdSe optical parametric oscillator in the 9-10 microm region

Area of Science:

• Nonlinear Optics
• Laser Physics
• Materials Science

Background:

• Optical parametric oscillators (OPOs) are crucial for generating tunable laser light.
• Singly resonant OPOs (SPOPOs) offer advantages in efficiency and stability.
• Cadmium Selenide (CdSe) is explored as a nonlinear optical material.

Purpose of the Study:

• To demonstrate continuous mode-locked operation of a CdSe-based SPOPO.
• To achieve tunable idler output in the mid-infrared region.
• To investigate the potential for power scaling and extended tuning ranges.

Main Methods:

• Utilized a singly resonant, synchronously pumped optical parametric oscillator (SPOPO) configuration.
• Employed Cadmium Selenide (CdSe) as the nonlinear gain medium.
• Implemented tandem pumping with a tunable parametric oscillator in periodically poled lithium niobate for agile tuning.

Main Results:

• Achieved continuous mode-locked operation with idler output tuned from 9.1 to 9.7 micrometers.
• Generated average idler powers up to approximately 70 mW within the CdSe crystal.
• Observed no detrimental thermal effects in the CdSe crystal, indicating potential for power scaling.

Conclusions:

• The CdSe-based SPOPO represents a significant advancement in generating long-wavelength idler output.
• The demonstrated tuning range and power levels are the longest and highest reported for a SPOPO.
• The absence of thermal issues suggests future scalability for broader tuning (8-12 micrometers).