SINGLE-FREQUENCY, SINGLE-SPATIAL-MODE ROW-DFB DIODE-LASER ARRAYS

Single-frequency, stable single-spatial-mode operation from large-aper ture (40-60 mu m) index-guided devices is demonstrated from resonant a ntiguided phase-locked InGaAs-InGaP-GaAs diode-laser arrays incorporat ing 2nd-order distributed-feedback gratings (i.e., ROW-DFB arrays), Th e devices operate in a single-spatial-mode up to 3.6 x threshold, and truly single-mode (i.e., single-spatial-mode and single-frequency) up to 2 x threshold, For 40 (60)-mu m-aperture 10-element arrays, the bea m pattern is in-phase and diffraction-limited with 70% (75%) of the po wer residing in the main lobe. Single-frequency operation is obtained from 9640-9652 Angstrom, over a temperature range of approximately 20 degrees C,. Side-mode suppression ratios greater than or equal to 20 d B are recorded up to 2 x threshold.