title: High efficiency coherent beam combining of semiconductor optical amplifiers.
abstract: We demonstrate 40 W coherently combined output power in a single diffraction-limited beam from a one-dimensional 47-element array of angled-facet slab-coupled optical waveguide amplifiers at 1064 nm. The output from each emitter was collimated and overlapped onto a diffractive optical element combiner using a common transform lens. Phase locking was achieved via active feedback on each amplifier's drive current to maximize the power in the combined beam. The combining efficiency at all current levels was nearly constant at 87%.
authors.affiliation: MIT Lincoln Laboratory, Lexington, Massachusetts 02420, USA. kevin.creedon@ll.mit.edu
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Creedon
authors.forename: Shawn M
authors.initials: SM
authors.lastname: Redmond
authors.forename: Gary M
authors.initials: GM
authors.lastname: Smith
authors.forename: Leo J
authors.initials: LJ
authors.lastname: Missaggia
authors.forename: Michael K
authors.initials: MK
authors.lastname: Connors
authors.forename: Jan E
authors.initials: JE
authors.lastname: Kansky
authors.forename: Tso Yee
authors.initials: TY
authors.lastname: Fan
authors.forename: George W
authors.initials: GW
authors.lastname: Turner
authors.forename: Antonio
authors.initials: A
authors.lastname: Sanchez-Rubio