Watt-level, all-fiber, ultrafast Er/Yb-codoped double-clad fiber laser mode-locked by reduced graphene oxide interacting with a weak evanescent field

TL;DR

This paper presents a Watt-level, all-fiber ultrafast laser using reduced graphene oxide as a saturable absorber, achieving stable 573 fs pulses with high power, thermal stability, and low nonlinearity.

Contribution

It introduces a novel all-fiber mode-locked laser employing rGO interacting via evanescent fields, enhancing thermal damage threshold and reducing nonlinearity.

Findings

Achieved 1.14 W average output power.

Generated stable 573 fs soliton pulses.

Enhanced thermal stability and reduced nonlinearity.

Abstract

We propose a Watt-level, all-fiber, ultrafast Er/Yb-codoped double-clad fiber laser passively mode-locked by reduced graphene oxide (rGO) interacting with a weak evanescent field of photonic crystal fiber (PCF). The rGO solution is filled into the cladding holes of the PCF based on total reflection, and after evaporation, the rGO flakes bear only 1/107 of the total energy in laser system, which enhances the thermal damage threshold and decreases the accumulated nonlinearity. By incorporating the saturable absorber into an Er/Yb-codoped fiber ring cavity, stable conventional soliton with a duration of 573 fs is generated, and a average output power up to 1.14 W is obtained.