Tunable and switchable multi-wavelength erbium-doped fiber ring laser based on a modified dual-pass Mach-Zehnder interferometer

TL;DR

This paper presents a novel tunable multi-wavelength erbium-doped fiber ring laser with switchable operation, enabling flexible control over lasing lines and wavelengths using a modified dual-pass Mach-Zehnder interferometer.

Contribution

A new tunable comb filter design allowing simultaneous wavelength switching and channel spacing tuning in erbium-doped fiber lasers.

Findings

Achieved up to 29 stable lasing lines with 0.4 nm spacing

Demonstrated 14 lasing wavelengths with 0.8 nm spacing

Flexible adjustment of lasing characteristics via polarization control

Abstract

A tunable and switchable multi-wavelength erbium-doped fiber ring laser based on a new type tunable comb filter is proposed and demonstrated. By adjusting the polarization controllers, dual-function operation of the channel spacing tunability and the wavelength switching (interleaving) can be readily achieved. Up to 29 stable lasing lines with 0.4 nm spacing and 14 lasing wavelengths with 0.8 nm spacing in 3 dB bandwidth were obtained at room temperature. In addition, the lasing output, including the number of the lasing lines, the lasing evenness and the lasing locations, can also be flexibly adjusted through the wavelength-dependent polarization rotation mechanism.