title: Continuous-wave two-photon absorption in a Watt-class semiconductor optical amplifier.
abstract: We report the observation of photoluminescence produced by the recombination of free carriers generated via continuous-wave (CW) two-photon absorption (TPA) in a packaged, low-confinement (Gamma approximately 0.5%) InGaAsP/InP quantum-well slab-coupled optical waveguide amplifier (SCOWA) having a saturation output power of 0.8 W and 1/e-mode-field diameters of 5 x 7 microm. Photoluminescence power measured at the wavelength corresponding to the bandgap wavelength of the SCOWA's InGaAsP waveguide (lambda(G) approximately 1040 nm) exhibits a quadratic dependence on the amplifier's 1540-nm output power. Comparison between measured and simulated CW gain saturation data reveals that the combination of TPA and TPA-generated free-carrier absorption (FCA) limits the CW output intensity of high-power, low-confinement semiconductor optical amplifiers and semiconductor lasers.
authors.affiliation: Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02420, USA. juodawlkis@ll.mit.edu
authors.forename: Paul W
authors.initials: PW
authors.lastname: Juodawlkis
authors.forename: Jason J
authors.initials: JJ
authors.lastname: Plant
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Donnelly
authors.forename: Ali
authors.initials: A
authors.lastname: Motamedi
authors.forename: Erich P
authors.initials: EP
authors.lastname: Ippen
mesh_terms: D000669:Amplifiers, Electronic; D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D008962:Models, Theoretical; D055095:Optics and Photonics / Q000295:instrumentation*; D017785:Photons; D012666:Semiconductors