title: Analysis of broadly tunable coupled-cavity semiconductor lasers.
abstract: We report on the spectral properties for above-threshold operation of broadly tunable, asymmetric multiple quantum well (AMQW), coupled-cavity InGaAsP/InP semiconductor diode lasers. We developed a traveling wave model to understand the mode selection that the lasers exhibit. We find that a weak, short external cavity (SXC) can be used to obtain single frequency operation on each longitudinal mode over the ∼100 nm tuning range of the uncoated AMQW coupled-cavity lasers. We measured the spectral properties of AMQW coupled-cavity lasers with and without an SXC. In a synthesized optical coherent optical tomography application, the use of an SXC with an AMQW coupled-cavity laser reduces the coherence length and hence enhances the performance of the AMQW coupled-cavity laser for optical coherence tomography applications.
authors.affiliation: Department of Engineering Physics, McMaster University, 1280 Main Street West, JHE-A315, Hamilton, Ontario L8S 4L7 Canada.
authors.forename: Ferdous K
authors.initials: FK
authors.lastname: Khan
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Cassidy