Systems and methods for stripping an optical mode from a semiconductor
laser. A waveguide layer is included in the semiconductor laser and is
typically arranged beneath the active region. The waveguide layer is
configured to match the phase of the second order mode. The waveguide
layer does not substantially match the primary optical mode of the laser.
By matching the phase of the second order mode, the confinement of the
second order mode is reduced and the second order mode strongly couples
with the waveguide layer. The optical confinement of the primary mode is
not substantially reduced. The side-mode suppression ratio is thereby
improved by stripping the second order mode from the active region.