Ultrafast thulium-doped fiber-oscillator with pulse energy of 43 nJ

Abstract

A femtosecond fiber laser based on thulium-doped double-clad silica fiber with an internal dispersion compensation is presented that generates pulses at a center wavelength of $1976\mathrm{nm}$ with an energy of $4.3\mathrm{nJ}$ and a duration of $1.2\mathrm{ps}$. The dechirped pulse duration is $294\mathrm{fs}$. The pulse energy is more than 2 orders of magnitude above the pulse energy demonstrated previously. Mode locking is achieved using additive pulse mode locking, and dispersion compensation is facilitated by a grating stretcher arrangement.