Abstract

To prevent the thermally induced spatial beam degradation occurring in high-power fiber lasers and amplifiers, index-depressed core “fully aperiodic large-pitch fibers” (FA-LPFs) have been designed and fabricated. In contrast to previous experimental works performed on FA-LPFs, in which the active core and the surrounding cladding material are quasi-index-matched, the core refractive index is in slight depression compared to the surrounding material ($\Delta n \approx - {3} \times {{10}^{- 5}}$). Thus, the index-depressed fiber core tends first to behave as an anti-guide, preventing light from being properly guided into it. However, by increasing the absorbed pump power, the thermal load induces a parabolic refractive index change sufficient to compensate for the ${-3} \times {{10}^{- 5}}$ index depression in the core, enabling a robust single-mode amplification at high average power. As a proof of concept, using a 110 µm depressed core FA-LPF, ${M^2}$ values of 1.3 were demonstrated in amplifier configuration from 60 W to a maximal value of 170 W of emitted average power only limited by the available pump power.

© 2021 Optical Society of America

Full Article  |  PDF Article
More Like This
Experimental study of the mode instability onset threshold in high-power FA-LPF lasers

Marie-Alicia Malleville, Romain Dauliat, Aurélien Benoît, Baptiste Leconte, Dia Darwich, Rémi du Jeu, Raphaël Jamier, Kay Schuster, and Philippe Roy
Opt. Lett. 42(24) 5230-5233 (2017)

Precompensation of the thermal-induced refractive index changes into a fully aperiodic LPF for heat load resilience

Dia Darwich, Romain Dauliat, Raphaël Jamier, Aurélien Benoit, Kay Schuster, and Philippe Roy
Appl. Opt. 55(29) 8213-8220 (2016)

Demonstration of a homogeneous Yb-doped core fully aperiodic large-pitch fiber laser

Romain Dauliat, Aurélien Benoît, Dia Darwich, Raphaël Jamier, Jens Kobelke, Stephan Grimm, Kay Schuster, and Philippe Roy
Appl. Opt. 55(23) 6229-6235 (2016)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Data Availability

Data underlying the results presented in this paper are not publicly available at this time but may be obtained from the authors upon reasonable request.

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (5)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription