title: Merged beam laser design for reduction of gain-saturation and two-photon absorption in high power single mode semiconductor lasers.
abstract: In this paper we report a method to overcome the limitations of gain-saturation and two-photon absorption faced by developers of high power single mode InP-based lasers and semiconductor optical amplifiers (SOA) including those based on wide-waveguide or slab-coupled optical waveguide laser (SCOWL) technology. The method is based on Y-coupling design of the laser cavity. The reduction in gain-saturation and two-photon absorption in the merged beam laser structures (MBL) are obtained by reducing the intensity of electromagnetic field in the laser cavity. Standard ridge-waveguide lasers and MBLs were fabricated, tested and compared. Despite a slightly higher threshold current, the reduced gain-saturation in MBLs results in higher output power. The MBLs also produced a single spatial mode, as well as a strongly dominating single spectral mode which is the inherent feature of MBL-type cavity.
authors.affiliation: Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200, Australia. lmb109@physics.anu.edu.au
authors.forename: M
authors.initials: M
authors.lastname: Lysevych
authors.forename: H H
authors.initials: HH
authors.lastname: Tan
authors.forename: F
authors.initials: F
authors.lastname: Karouta
authors.forename: L
authors.initials: L
authors.lastname: Fu
authors.forename: C
authors.initials: C
authors.lastname: Jagadish
mesh_terms: D000042:Absorption; D000669:Amplifiers, Electronic; D004867:Equipment Design; D019544:Equipment Failure Analysis; D054023:Lasers, Semiconductor; D017785:Photons