Abstract

Injection of a signal from a single spatial and spectral mode master laser diode can be used to control the spectral characteristics of a narrow stripe slave laser and to establish phase coherence between multiple lasers. With high power large active area laser diodes such as coupled stripe arrays, external injection can also control the near field phase distribution and, therefore, the far field diffraction pattern of the laser.^1–3 As a result, diffraction-limited and single spectral mode emission has been demonstrated in 0.5-1.0-W laser arrays and broad stripe⁴ GaAlAs lasers which operated with wide diffraction patterns when free running. A typical injection-locking arrangement and the resulting laser far field are shown in Figs. 1 and 2.

© 1990 Optical Society of America