Abstract
We present a model for a Yb-doped distributed Bragg reflector (DBR) waveguide laser fabricated in phosphate glass using the femtosecond laser direct-write technique. The model gives emphasis to transverse integrals to investigate the energy distribution in a homogenously doped glass, which is an important feature of femtosecond laser inscribed waveguide lasers (WGLs). The model was validated with experiments comparing a DBR WGL and a fiber laser, and then used to study the influence of distributed rare earth dopants on the performance of such lasers. Approximately 15% of the pump power was absorbed by the doped "cladding" in the femtosecond laser inscribed Yb doped WGL case with the length of 9.8 mm. Finally, we used the model to determine the parameters that optimize the laser output such as the waveguide length, output coupler reflectivity and refractive index contrast.
Highlights
The advent of the femtosecond laser direct-write technique offers promising opportunities for realizing all-optical devices [1]
In conclusion we have developed a predictive, rate equation model for distributed Bragg reflector (DBR) waveguide lasers fabricated using the femtosecond laser direct-write technique
The model accounts for the presence of a homogeneously distributed rare earth dopant, and was validated by analyzing a conventional fiber laser and an ultrafast laser inscribed waveguide laser
Summary
The advent of the femtosecond laser direct-write technique offers promising opportunities for realizing all-optical devices [1] It enables simple creation of compact 3D structures in transparent materials with greater flexibility than traditional fabrication methods involving ion exchange or photolithography. We present a detailed characterization of a DBR waveguide laser fabricated by a femtosecond laser and a numerical model to analyze the laser performance This model is based on rate equations, combined with the transverse integration of the propagating mode field and was validated with an experimental comparison of a DBR fiber laser and WGL. The doped cladding region of the DBR waveguide laser absorbed approximately 15% of the pump power
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have