Multi-wavelength Yb:YAG/Nd³⁺:YVO₄ continuous-wave microchip Raman laser.

Area of Science:

• Laser Physics
• Nonlinear Optics
• Solid-State Lasers

Background:

• Continuous-wave (CW) Raman lasers are crucial for various applications, including Terahertz (THz) generation.
• Microchip lasers offer compact and efficient laser sources.
• Developing multi-wavelength capabilities in microchip Raman lasers enhances their functionality.

Purpose of the Study:

• To demonstrate multi-wavelength continuous-wave (CW) Raman lasers in a laser diode-pumped Yb:YAG/Nd:YVO4 microchip system for the first time.
• To investigate the generation of first Stokes radiation at approximately 1.08 μm with a specific Raman shift.
• To explore the tunability of multi-wavelength operation and frequency separation for potential THz generation applications.

Main Methods:

• Utilized a laser diode-pumped Yb:YAG/Nd:YVO4 microchip Raman laser.
• Employed an a-cut Nd:YVO4 crystal to achieve Raman shifts.
• Varied incident pump power to control multi-wavelength operation and frequency separation.

Main Results:

• Achieved multi-wavelength laser operation simultaneously around 1.05 μm and 1.08 μm.
• Demonstrated multi-wavelength Raman laser operation with a frequency separation of 1 THz at pump powers above 1.7 W.
• Obtained a maximum Raman laser output power of 260 mW at 1.08 μm with an optical-to-optical conversion efficiency of 4.2%.
• Observed elliptically polarized fundamental laser and linearly polarized Raman laser output.

Conclusions:

• The successful demonstration of multi-wavelength CW microchip Raman lasers provides a novel approach for compact laser sources.
• Adjustable frequency separation in these lasers is key for developing advanced applications like Terahertz generation.
• This work opens new avenues for efficient and tunable laser systems in nonlinear optics and photonics.