Graded-gain dye laser amplifiers: an experimental investigation

Area of Science:

• Laser Physics
• Nonlinear Optics
• Photonic Devices

Background:

• Inhomogeneous gain and refractive index distributions from pumping radiation can significantly impact dye laser amplifier performance.
• Understanding these effects is crucial for optimizing laser output and efficiency.

Purpose of the Study:

• To investigate the influence of inhomogeneous gain and refractive index on dye laser amplifier performance.
• To experimentally measure gain factors and saturated gain in various amplifier configurations.

Main Methods:

• Experimental measurements were conducted using capillary cylindrical and planar cells.
• Single-pass, double-pass, and ring amplifier configurations were tested.
• Rhodamine 6G in ethanol was used as the gain medium.

Main Results:

• Gain factors as high as 8.5 x 10^4 were achieved at low signal input.
• A saturated gain of 5 x 10^3 was obtained at 100-mJ output.
• An overall efficiency of 0.1% was achieved without full parameter optimization.

Conclusions:

• Dye laser amplifiers are sensitive to pumping-induced inhomogeneities.
• A two-stage double-pass amplifier can serve as an efficient high-energy light source.
• Further optimization of amplifier parameters can potentially enhance performance.