Efficient Raman converter in the yellow range with high spatial and spectral brightness

Area of Science:

• Optics and Photonics
• Nonlinear Optics
• Laser Technology

Background:

• Efficient generation of visible light is crucial for various applications.
• Raman conversion offers a pathway to spectral tailoring of laser sources.
• Sub-nanosecond pulsed lasers enable high peak power applications.

Purpose of the Study:

• To demonstrate a Raman converter emitting at 583 nm.
• To achieve high conversion efficiency and spectral brightness in the visible range.
• To characterize the performance of a sub-nanosecond Raman converter.

Main Methods:

• Utilized propan-2-ol as the Raman medium.
• Employed a 532 nm sub-nanosecond microlaser as the pump source.
• Adapted a photonic bandgap fiber using a liquid mixture for optimal transmission.

Main Results:

• Achieved 67% internal conversion efficiency in photon numbers at 583 nm (second Stokes order).
• Generated an output power of 1.06 mW with a maximum peak power of 338 W.
• Delivered a beam with Gaussian spatial structure and high spectral brightness, exceeding supercontinuum sources by over five times.

Conclusions:

• The developed Raman converter provides an efficient method for generating visible light at 583 nm.
• The system's high spectral brightness makes it suitable for applications requiring high-quality visible laser sources.
• This work demonstrates the potential of liquid-filled photonic bandgap fibers for efficient nonlinear frequency conversion.