Xinhuan Feng

Stable and uniform multiwavelength erbium-doped fiber laser using nonlinear polarization rotation

A novel and simple technique, based on nonlinear polarization rotation (NPR) effect, to generate stable multiwavelength oscillations in an erbium-doped fiber laser is proposed and successfully demonstrated. The NPR effect effectively induced intensity- and wavelength-dependent loss to alleviate mode competition caused by homogeneous gain broadening in erbium-doped fibers. Up to 28-wavelength lasing operation with wavelength spacing of 0.8 nm has been achieved. The outputs had uniform power distributions, and the power fluctuation in each wavelength is smaller than 0.2 dB within a period of an hour.

Single-longitudinal-mode lanthanum-codoped bismuth-based erbium doped fiber ring laser

We propose and demonstrate a stable single-longitudinal-mode lanthanum-codoped bismuth oxide-based erbium doped fiber ring laser. The combination of a free-space thin-film filter and a Lyot filter enable single longitudinal mode efficiency.

Spectrum engineering of multiwavelength erbium doped fiber lasers with intensity-dependent loss

We studied multiwavelength erbium-doped fiber lasers with intensity-dependent loss using rate equations. Pump power, cavity loss and the parameters of the intensity-dependent loss are varied to engineer the lasing spectrum. Experiments agree with simulation results.

Modeling of multiwavelength laser with saturable homogeneous gain and nonlinear loss

We theoretically studied the operation of a laser with homogeneous gain and nonlinear loss. Multi-wavelength operation is possible because the nonlinear loss provides an adaptive balance to the different gain values at different wavelengths.

Nonlinear dynamics in lasers with nonlinear loss

We study the dynamics of lasers with nonlinear loss theoretically. Our simulations show that depending on the laser parameters, the laser output can exhibit stable, periodic bifurcation, or chaotic behavior.

Ultra-flat spectrum, multiwavelength operation in an erbium-doped fiber laser using power-clamping effect

A novel mechanism which utilizes power-clamping effect to realize stable and uniform multiwavelength oscillations in an EDFL is proposed and demonstrated. Up to 50 wavelengths oscillations with wavelength spacing of 0.8 nm has been achieved.