1. Institute of Electrical Engineering, Slovak Academy of Sciences, Bratislava, Slovakia
2. CIMAP, UMR 6252 CNRS, 6 Boulevard Maréchal Juin, 14050 Caen, France
3. Center for Device Thermography and Reliability, University of Bristol, Bristol BS8 1TL, UK
4. University Science Park Bratislava Centre, Slovak University of Technology, Vazovova 5, 812 43 Bratislava, Slovakia
5. International Laser Centre, Ilkovičova 3, Bratislava, Slovakia
6. Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, 02-668 Warsaw, Poland
7. Institute of Physics, Slovak Academy of Sciences, Dúbravská cesta 9, 845 11 Bratislava 45, Slovak Republic