Matching of the propagation constants in an asymmetric single-mode fused fiber coupler for core pumping thulium-doped fiber at 795 nm.
We developed a fused fiber coupler (FFC) capable of multiplexing wavelengths in the range of 795 nm and 2 μm. A simple 2D simulation model to calculate the pretaper length for matching the propagation constants in the coupling region was established. Based on the numerical data, we fabricated an asymmetric FFC consisting of two different fibers with single-mode guidance for the respective wavelength, achieving a transmission of 90% in the signal fiber for both wavelengths. In order to demonstrate the application, we integrated the FFC into a core pumped thulium-doped fiber amplifier.
Laser Zentrum Hannover e.V., Hollerithallee 8, D-30419 Hannover, Germany. g.pelegrina@lzh.de
Gabriel
G
Pelegrina-Bonilla
Katharina
K
Hausmann
Kai
K
Liu
Hakan
H
Sayinc
Uwe
U
Morgner
Jörg
J
Neumann
Dietmar
D
Kracht
D007834:Lasers; D055100:Optical Fibers; D055620:Optical Phenomena; D013932:Thulium
D013932:Thulium