Laser degradation, due to the formation of misfit dislocations, was observed by means of X-ray topography. Laser diodes were driven under a high-energy high-flux synchrotron micro X-ray beam. The laser characteristic curve, and structural characteristics during operation, were monitored simultaneously. In some lasers, device degradation occurred via mass transport; without the formation of misfit dislocations.

Observation of Dislocation Generation in Highly Strained Quantum Well Lasers during Operation. A.Mazuelas, M.L.Dotor, D.Golmayo, U.Zeimer, T.Baumbach, D.Luebbert, J.Grenzer, J.Baruchel: Journal of Physics D, 2001, 34[SA], 117-21