S
Sigrun Hein
Researcher at Fraunhofer Society
Publications - 34
Citations - 449
Sigrun Hein is an academic researcher from Fraunhofer Society. The author has contributed to research in topics: Ytterbium & Laser. The author has an hindex of 7, co-authored 25 publications receiving 328 citations.
Papers
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Journal ArticleDOI
Single mode 4.3 kW output power from a diode-pumped Yb-doped fiber amplifier.
Franz Beier,Christian Hupel,Stefan Kuhn,Sigrun Hein,Johannes Nold,F Proske,Bettina Sattler,Andreas Liem,Cesar Jauregui,Jens Limpert,Nicoletta Haarlammert,Thomas Schreiber,Ramona Eberhardt,Andreas Tünnermann +13 more
TL;DR: A high slope efficiency of 90% with diffraction-limited beam quality and without any sign of TMI or stimulated Raman scattering for a spectral dynamic range of higher than -80 dB was obtained.
Journal ArticleDOI
Narrow linewidth, single mode 3 kW average power from a directly diode pumped ytterbium-doped low NA fiber amplifier
Franz Beier,Christian Hupel,Johannes Nold,Stefan Kuhn,Sigrun Hein,J Ihring,Bettina Sattler,Nicoletta Haarlammert,Thomas Schreiber,Ramona Eberhardt,Andreas Tünnermann +10 more
TL;DR: A newly designed and fabricated ytterbium-doped large mode area fiber with an extremely low NA and related systematic investigations on fiber parameters that crucially influence the mode instability threshold are reported on.
Journal ArticleDOI
Experimental investigations on the TMI thresholds of low-NA Yb-doped single-mode fibers
Franz Beier,Friedrich Möller,Bettina Sattler,Johannes Nold,Andreas Liem,Christian Hupel,Stefan Kuhn,Sigrun Hein,Nicoletta Haarlammert,Thomas Schreiber,Ramona Eberhardt,Andreas Tünnermann +11 more
TL;DR: This contribution investigates the transversal mode instability behavior of a ytterbium-doped commercial 20/400 fiber and obtains 2.9 kW of output power after optimizing the influencing parameters.
Journal ArticleDOI
Laser cooling of ytterbium-doped silica glass
Esmaeil Mobini,Saeid Rostami,Mostafa Peysokhan,Alexander R. Albrecht,Stefan Kuhn,Sigrun Hein,Christian Hupel,Johannes Nold,Nicoletta Haarlammert,Thomas Schreiber,Ramona Eberhardt,Andreas Tünnermann,Andreas Tünnermann,Mansoor Sheik-Bahae,Arash Mafi +14 more
TL;DR: In this article, the authors show the net cooling of high-purity Yb-doped silica glass samples that are fabricated with low impurities to reduce their parasitic background loss for fiber laser applications.
Journal ArticleDOI
Implementation of Laser-Induced Anti-Stokes Fluorescence Power Cooling of Ytterbium-Doped Silica Glass.
Mostafa Peysokhan,Saeid Rostami,Esmaeil Mobini,Alexander R. Albrecht,Stefan Kuhn,Sigrun Hein,Christian Hupel,Johannes Nold,Nicoletta Haarlammert,Thomas Schreiber,Ramona Eberhardt,Angel Flores,Andreas Tünnermann,Andreas Tünnermann,Mansoor Sheik-Bahae,Arash Mafi +15 more
TL;DR: More than 6 K of cooling below the ambient temperature is reported, which is the lowest temperature achieved in solid-state laser cooling of silica glass to date to the best of the authors' knowledge.