Injection locking characteristics of a 1 W broad stripe laser diode

Abstract

Single narrow far-field lobe emission is observed in an injection-locked high-power broad stripe laser. Lobe widths below 1.3 times the diffraction limit for the 160-μm-wide stripe were observed for power levels up to 1.0 W. Decrease in the power contained within the narrow lobe for high laser bias currents is observed and is attributed to self-focusing effects in the active region. Small-signal external power gain of 21 dB was measured.

Power dependence of the injection lock band of angled-grating distributed feedback lasers

“…Theoretical models of injection locking in semiconductor lasers have been developed which have been successful in predicting many features of an injection-locked laser system such as the asymmetric locking characteristic, and the existence of an unstable lock region. [7][8][9] The best performance reported, with a high power single lobed far field, was obtained up to 3.8ϫI th , limited by the onset of filamentation. 5,6 In addition, several authors have studied the near field and far field behavior of broad area semiconductor lasers under optical injection.…”

Improvement of spatial and temporal coherence of a broad area laser diode using an external-cavity design with double grating feedback

“…Several techniques, such as injection locking [7][8][9] with an external single-mode source and various external cavities have been developed in order to control the emission from BALs and LDAs. A common way to improve the spatial and/or temporal coherence of the LD is the use of off-axis external reflectors such as conventional mirrors [10][11][12][13][14], diffraction gratings [16,17], or phase conjugators [17][18][19] combined with spatial and/or spectral filtering.…”

Intrinsic beam shaping mechanism in spatially modulated broad area semiconductor amplifiers

“…Several approaches have been proposed and applied to improve the spatial quality of the radiation, each, however, with its disadvantages. For example, different schemes of optical injection 5,6 and optical feedback, 7,8 or integrated narrow master oscillator-tapered power amplifier configurations 9,10 improve the beam quality, however, in return, the laser becomes less compact or is rather sensitive to the back reflections.…”