A waveguide (10) is provided having a two-dimensional optical wavelength
Bragg grating (20) embedded within a semiconductor laser medium (16). More
particularly, the waveguide (10) includes an active region (16) sandwiched
between n-doped and p-doped cladding layers (14, 22). The two-dimensional
Bragg grating (20) is formed in the active region (16). Upper and lower
electrodes (24, 26) are defined on opposite sides of the cladding layers
(14, 22) to complete the waveguide structure (10). The two-dimensional
grating (20) provides simultaneous frequency selective feedback for mode
control in both the longitudinal and lateral directions.