| Image data | |
| Image size: | 10 x 10 µm |
| Temperature: | App. 50K |
| Number of points: | 128 x 128 in x,y; 1024 in Z (Wavelength) |
| Total data size: | 33,5 MB |
| Spatially integrated opt. spectrum: |  |
Simultaneously measured information:
The sample consists of laterally grown layers with low defect density and vertically grown layers with higher defect density. The defects work as non radiative recombination centers, resulting in a strongly reduced luminescence around these. In the SNOM measurement it can be seen that the laterally grown layers are significantly brighter than the vertically grown layers. Comparison with the (simultaneously recorded) topography image to the right shows that groves in the topography lie exactly in the middle of the laterally grown zones. (see F. Hitzel et al., Appl. Phys. Lett. 82, 4071 (2003) )
In the video it is clearly seen how the structure information is only visible for wavelengths within the emission peak. There are no reflections or similar effects that may cause a signal independent of the wavelength. It is one of the features of nearfield spectroscopy that through the wavelength sensitivity it is possible to distinguish between noise signals and real information.