TY - GEN
T1 - Power scaling of a hybrid microstructured Yb-doped fiber amplifier
AU - Mart, Cody
AU - Pulford, Benjamin
AU - Ward, Benjamin
AU - Dajani, Iyad
AU - Ehrenreich, Thomas
AU - Anderson, Brian
AU - Kieu, Khanh
AU - Sanchez, Tony
N1 - Publisher Copyright:
© 2017 SPIE.
PY - 2017
Y1 - 2017
N2 - Hybrid microstructured fibers, utilizing both air holes and high index cladding structures, provide important advantages over conventional fiber including robust fundamental mode operation with large core diameters (>30μm) and spectral filtering (i.e. amplified spontaneous emission and Raman suppression). This work investigates the capabilities of a hybrid fiber designed to suppress stimulated Brillouin scattering (SBS) and modal instability (MI) by characterizing these effects in a counter-pumped amplifier configuration as well as interrogating SBS using a pump-probe Brillouin gain spectrum (BGS) diagnostic suite. The fiber has a 35 μm annularly gain tailored core, the center doped with Yb and the second annulus comprised of un-doped fused silica, designed to optimize gain in the fundamental mode while limiting gain to higher order modes. A narrow-linewidth seed was amplified to an MI-limited 820 W, with near-diffraction-limited beam quality, an effective linewidth ∼ 1 GHz, and a pump conversion efficiency of 78%. Via a BGS pump-probe measurement system a high resolution spectra and corresponding gain coefficient were obtained. The primary gain peak, corresponding to the Yb doped region of the core, occurred at 15.9 GHz and had a gain coefficient of 1.92×10-11 m/W. A much weaker BGS response, due to the pure silica annulus, occurred at 16.3 GHz. This result demonstrates the feasibility of power scaling hybrid microstructured fiber amplifiers.
AB - Hybrid microstructured fibers, utilizing both air holes and high index cladding structures, provide important advantages over conventional fiber including robust fundamental mode operation with large core diameters (>30μm) and spectral filtering (i.e. amplified spontaneous emission and Raman suppression). This work investigates the capabilities of a hybrid fiber designed to suppress stimulated Brillouin scattering (SBS) and modal instability (MI) by characterizing these effects in a counter-pumped amplifier configuration as well as interrogating SBS using a pump-probe Brillouin gain spectrum (BGS) diagnostic suite. The fiber has a 35 μm annularly gain tailored core, the center doped with Yb and the second annulus comprised of un-doped fused silica, designed to optimize gain in the fundamental mode while limiting gain to higher order modes. A narrow-linewidth seed was amplified to an MI-limited 820 W, with near-diffraction-limited beam quality, an effective linewidth ∼ 1 GHz, and a pump conversion efficiency of 78%. Via a BGS pump-probe measurement system a high resolution spectra and corresponding gain coefficient were obtained. The primary gain peak, corresponding to the Yb doped region of the core, occurred at 15.9 GHz and had a gain coefficient of 1.92×10-11 m/W. A much weaker BGS response, due to the pure silica annulus, occurred at 16.3 GHz. This result demonstrates the feasibility of power scaling hybrid microstructured fiber amplifiers.
KW - Mode Instability
KW - Photonic Bandgap Fiber
KW - Photonic Crystal Fiber
KW - Stimulated Brillouin Scattering
UR - http://www.scopus.com/inward/record.url?scp=85019404821&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85019404821&partnerID=8YFLogxK
U2 - 10.1117/12.2249863
DO - 10.1117/12.2249863
M3 - Conference contribution
AN - SCOPUS:85019404821
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Fiber Lasers XIV
A2 - Hartl, Ingmar
A2 - Robin, Craig A.
PB - SPIE
T2 - Fiber Lasers XIV: Technology and Systems 2017
Y2 - 30 January 2017 through 2 February 2017
ER -