Cryogenically monolithic self-Raman lasers: observation of single-longitudinal-mode operation

Area of Science:

• Laser Physics
• Nonlinear Optics
• Materials Science

Background:

• Cryogenic cooling offers enhanced performance in solid-state lasers.
• Thermal lensing effects can degrade laser performance.
• Stimulated Raman Scattering (SRS) provides wavelength conversion in lasers.

Purpose of the Study:

• To experimentally investigate and theoretically analyze a cryogenically monolithic Nd:YVO4 self-Raman laser.
• To understand the temperature dependence of the SRS threshold.
• To optimize SRS output power and achieve single-longitudinal-mode operation.

Main Methods:

• Experimental setup of a monolithic Nd:YVO4 self-Raman laser.
• Variable temperature control from 285 K down to 80 K.
• Theoretical analysis of thermal lensing and SRS threshold variations.

Main Results:

• Nonlinear relationship observed between SRS threshold and temperature due to reduced thermal lensing.
• SRS output power increased from 0.78 W to 1.36 W as temperature decreased from 285 K to 80 K.
• Single-longitudinal-mode operation achieved at temperatures below 125 K.

Conclusions:

• Cryogenic cooling is an effective method for enhancing the performance of Nd:YVO4 self-Raman lasers.
• Understanding temperature-dependent thermal lensing is crucial for optimizing SRS lasers.
• The developed laser system demonstrates potential for high-power, single-mode Raman generation.