All-fiber phase actuator based on an erbium-doped fiber amplifier for coherent beam combining at 1064 nm.

Laser Zentrum Hannover e V, Hannover, Germany.
Optics Letters (Impact Factor: 3.39). 02/2011; 36(4):448-50. DOI: 10.1364/OL.36.000448
Source: PubMed

ABSTRACT Active phase control in fiber amplifiers is of considerable interest for low-noise single-frequency amplifiers and for coherent beam combining. We demonstrate phase control at 1064 nm by use of an erbium-doped fiber. We investigated the phase shift by guiding the beam through an erbium-doped fiber amplifier in a Mach-Zehnder configuration and applied the results to stabilize the relative phase of two ytterbium-doped fiber amplifiers. To the best of our knowledge, this is the first demonstration of an all-fiber coherent beam combining at 1064 nm employing an erbium-doped fiber as a phase actuator.

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