title: Rear-side resonator architecture for the passive coherent combining of high-brightness laser diodes.
abstract: We describe a new coherent beam combining architecture based on passive phase locking of emitters in an extended cavity on the rear facet and their coherent combination on the front facet. This rear-side technique provides strong optical feedback for phase locking while maintaining a high electrical-to-optical efficiency. Two high-brightness high-power tapered laser diodes are coherently combined using a Michelson-based cavity. The combining efficiency is above 82% and results in an output power of 6.7 W in a nearly diffraction-limited beam with an M(4σ)(2)≤1.2. A semi-active automatic adjustment of the current enhances the long-term stability of the combination, while the short-term stability is passively ensured by the extended cavity. This new laser configuration exhibits the simplicity of passive self-organizing architectures while providing a power conversion efficiency of 27% that is comparable to master oscillator power amplifier architectures.
authors.forename: G
authors.initials: G
authors.lastname: Schimmel
authors.forename: I
authors.initials: I
authors.lastname: Doyen-Moldovan
authors.forename: S
authors.initials: S
authors.lastname: Janicot
authors.forename: M
authors.initials: M
authors.lastname: Hanna
authors.forename: J
authors.initials: J
authors.lastname: Decker
authors.forename: P
authors.initials: P
authors.lastname: Crump
authors.forename: G
authors.initials: G
authors.lastname: Blume
authors.forename: G
authors.initials: G
authors.lastname: Erbert
authors.forename: P
authors.initials: P
authors.lastname: Georges
authors.forename: G
authors.initials: G
authors.lastname: Lucas-Leclin