High performance at new FIR wavelengths from optically pumped CH(2)F(2)

Area of Science:

• Optics and Photonics
• Laser Physics
• Quantum Electronics

Background:

• Continuous-wave (cw) far-infrared (FIR) lasers are crucial for spectroscopy and materials science.
• Previous research identified limitations in the efficiency of optically pumped FIR lasers.
• The methyl fluoride (CH(2)F(2)) laser system showed potential for high performance but required further optimization.

Purpose of the Study:

• To investigate efficiency-limiting mechanisms in the CH(2)F(2) laser.
• To maximize the performance and output power of the CH(2)F(2) laser system.
• To discover new laser lines for expanded spectral coverage in the FIR region.

Main Methods:

• Conducted a parametric study of the CH(2)F(2) laser system.
• Employed various cavity designs and optimized output coupling.
• Utilized carbon dioxide (CO(2)) laser pumping to excite the CH(2)F(2) medium.
• Measured wavelengths and conversion efficiencies of generated FIR laser lines.

Main Results:

• Discovered five new carbon dioxide (CO(2)) pump lines and ten new far-infrared (FIR) laser lines.
• Achieved measured conversion efficiencies exceeding 30% of the theoretical maximum.
• Optimized output coupling for the 184.6 micrometer line, doubling output power compared to the 118.8 micrometer line.
• Observed a 33% conversion efficiency at the highest CO(2) pump power, indicating potential for further scaling.

Conclusions:

• The CH(2)F(2) laser demonstrates exceptional performance as an optically pumped FIR laser.
• The discovered lines fill spectral gaps, enhancing the utility of FIR laser sources.
• The system's high efficiency and power scaling potential confirm its status as the strongest reported cw optically pumped FIR laser.