Five-mode erbium-doped waveguide amplifiers with low differential modal gain.

In this work, a five-mode erbium-doped waveguide amplifier with low differential modal gain (DMG) is first proposed. A novel, to the best of our knowledge, gain equalization scheme for synergistic reconfiguration of refractive index and concentration doping is adopted to equalize the modal gains based on the dual-layer ring core structure. NaYF:5%Gd,20%Yb,2%Er@NaYF nanoparticles are synthesized by annealing treatment to improve the emission spectral properties and the concentration doped in a host core material.

Improvement of differential modal gain in a ring-core few-mode erbium-doped polymer optical waveguide amplifier.

A few-mode erbium-doped waveguide amplifier (FM-EDWA) with a confined Er doped ring structure is proposed to equalize the differential modal gain (DMG). The FM-EDWA amplifying three spatial modes (LP, LP and LP) is optimized by genetic algorithm and fabricated using precise lithography overlay alignment technology. We observe gain values of over 14 dB for all modes with DMG of 0.

Few-mode polymer waveguide amplifier with a dual-layer coronal refractive index profile.

A novel, to the best of our knowledge, few-mode waveguide amplifier with a dual-layer coronal core is first proposed. Reconfiguring the refractive index profile is adopted to equalize the modal gains pumped in a single mode. The polymer in terms of the prominent advantages of simple processing and the ease of adjusting refractive index is utilized.