High-power, low-noise, Yb-doped, cladding-pumped, three-level fiber sources at 980 nm

Area of Science:

• Fiber laser technology
• Optoelectronics
• Laser physics

Background:

• Development of high-power, single-mode fiber lasers is crucial for various applications.
• Existing fiber laser sources around 980 nm have limitations in power and efficiency.
• Yb-doped fibers offer potential for efficient laser operation in this spectral region.

Purpose of the Study:

• To demonstrate high-power, single-mode fiber laser and amplified spontaneous emission (ASE) sources emitting at 977 nm.
• To achieve record-breaking power and slope efficiency for single-mode fiber sources at approximately 980 nm.
• To characterize the performance and suitability of these sources for diverse applications.

Main Methods:

• Utilizing a cladding-pumped, Ytterbium (Yb)-doped fiber architecture.
• Employing a high numerical aperture (> 0.7) and a jacketed air-clad fiber design.
• Implementing a high-brightness pump source to drive the laser and ASE configurations.
• Measuring fiber-coupled, single-mode output power and slope efficiency.

Main Results:

• Achieved up to 1.4 W of fiber-coupled, single-mode output power.
• Obtained a maximum slope efficiency of 68%.
• Demonstrated record high power and efficiency for single-mode fiber lasers near 980 nm.
• Presented the first high-power amplified spontaneous emission (ASE) source results in this wavelength range.
• Measured relative intensity noise below -130 dB/Hz for both laser and ASE sources.

Conclusions:

• The developed Yb-doped fiber laser and ASE sources represent a significant advancement in high-power, single-mode operation at 977 nm.
• The high power and efficiency achieved are attributed to the optimized fiber design and high-brightness pumping.
• The low noise characteristics make these sources suitable for a broad spectrum of demanding applications.
• These results establish new benchmarks for fiber optic sources in the ~980 nm spectral region.