Title :
Spatial coherence and thermal lensing in broad-area semiconductor lasers
Author :
Callaghan, James R O ; Houlihan, John ; Voignier, Vincent ; Wu, Guan H. ; O´Neill, Eamonn ; McInerney, John G. ; Huyet, Guillaume
Author_Institution :
Dept. of Optoelectronics, Univ. of Ulm, Germany
Abstract :
Injection profiled broad-area edge-emitting semiconductor lasers demonstrate single transverse mode operation and near-diffraction-limited beam output when driven by pulsed pump current. Thermal effects arising from CW operation induce filamentary dynamics, thus degrading the beam. Transition from the stable nonthermal to the unstable CW regime is analyzed experimentally and numerically, and techniques to improve beam quality in the thermal regime, based on feedback or thermal profiling, are proposed.
Keywords :
gradient index optics; laser beams; laser feedback; laser stability; light coherence; quantum well lasers; thermal lensing; CW operation; Maxwell-Bloch equations model; beam quality; broad-area semiconductor lasers; edge-emitting lasers; epitaxial design; external heating; feedback profiling; filamentary dynamics; gain tailoring; graded-index separate-confinement heterostructure; injection profiled lasers; near-diffraction-limited beam output; pulsed pump current; single transverse mode operation; spatial coherence; thermal lensing; thermal profiling; Laser beams; Laser excitation; Laser modes; Laser transitions; Optical pulses; Pump lasers; Semiconductor lasers; Spatial coherence; Thermal degradation; Thermal lensing;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2003.820832
