Publications by Moritz Bartnick

Observation of modulation instability in a coherently driven active fiber ring resonator at 2 µm wavelength

We report the first, to our knowledge, observation of the nonlinear phenomenon known as modulation instability (MI) in a coherently driven fiber resonator pumped at 1972 nm. To compensate for the very high losses in this spectral region, we have integrated ...

2024

Thulium-doped fiber cavities for frequency comb generation at 2 micron

Moritz Bartnick

The invention of the laser in the 1960s heralded a new era in photonics. Owing to both, academic and industrial research, photonics technologies have long become part of our everyday life. This PhD thesis explores two subfields of laser technologies: Frequ ...

EPFL2024

Wavelength-stabilized figure-of-9 thulium-doped all-fiber laser emitting 560 fs pulses

Camille Sophie Brès, Moritz Bartnick, Gayathri Bharathan

We demonstrate a figure-of-9 all-fiber thulium-doped laser (TDFL) that generates 560 fs long pulses at 1948 nm wavelength. In order to achieve self-starting passive mode-locking, we utilize an in-fiber Faraday rotator to induce a nonreciprocal phase shift. ...

Iop Publishing Ltd2024

Polarization-multiplexed thulium-doped fiber laser for free-running dual-comb generation

Camille Sophie Brès, Moritz Bartnick, Gayathri Bharathan

We demonstrate a polarization-maintaining passively mode-locked thulium-doped fibre laser that can operate at two different repetition rates (dual-comb) simultaneously. Based on the presented approach, we observe beat notes with a free spectral range of 1. ...

2023

Wavelength-stabilized tunable mode-locked thulium-doped fiber laser beyond 2 mu m

Camille Sophie Brès, Moritz Bartnick, Gayathri Bharathan

We report the development of a widely tunable mode-locked thulium-doped fiber laser based on a robust chirped fiber Bragg grating (CFBG). By applying mechanical tension and compression to the CFBG, an overall tunability of 20.1 nm, spanning from 2022.1 nm ...

Optica Publishing Group2022

Tunable wavelength-stabilized mode-locked thulium-doped fiber laser beyond 2000nm

Camille Sophie Brès, Moritz Bartnick, Gayathri Bharathan

We demonstrate operation of a tunable mode-locked thulium-doped fiber laser, based on a wavelength-selective chirped fiber Bragg grating (CFBG). By applying strain to the CFBG, we shift its reflection band and can thereby tune the emission-wavelength of th ...

SPIE-INT SOC OPTICAL ENGINEERING2022