1 Correction to: Appl. Phys. B (2016) 122:113 https://doi.org/10.1007/s00340-016-6392-1

The Editor-in-Chief has retracted this article because post-publication review has shown that there are serious flaws with respect to the acquisition of data through the instrumentation used. The lack of sufficient information on experimental procedures makes it impossible to reproduce the author’s approach. For example, it is not defined which portion of light is analysed in the spectral measurements shown in the article. As a consequence the interpretation of the results (e.g. in terms of “microlasing”) must be considered unsound. The author does not agree with this retraction.