Low-coherence dye laser with an intracavity radiation diffuser.

Area of Science:

• Laser Physics
• Materials Science
• Optics

Background:

• Traditional dye lasers often produce highly coherent radiation.
• Achieving low-coherence laser output is crucial for specific applications like imaging and sensing.
• Developing new laser architectures is essential for advancing optical technologies.

Purpose of the Study:

• To investigate a novel dye laser design incorporating an intracavity diffuser.
• To characterize the spectral and spatial-angular properties of the developed low-coherence dye laser.
• To explore the tunability of spatial coherence in this slurry-based laser system.

Main Methods:

• A cuvette containing a slurry of LiF crystal granules and dye solution was used as the active medium and diffuser within a double flat mirror cavity.
• The system was pumped using 25 ns pulses from the 2nd harmonic of a Nd:YAG laser.
• Measurements of loss coefficients, ray deflection angles, spectral output, and spatial coherence were performed.

Main Results:

• The dye laser generated 20 ns pulses with energies around 1 mJ in the 550-650 nm range.
• Radiation exhibited significant beam divergence (5-80 mrad) and a low degree of spatial coherence (γ ≲ 0.1).
• Tuning of the spatial coherence of the laser output was successfully demonstrated.

Conclusions:

• The developed dye laser with an intracavity diffuser effectively produces low-coherence radiation.
• The system offers tunable spatial coherence, making it suitable for applications requiring controlled coherence.
• This approach presents a viable method for generating low-coherence laser sources.