D retention and material defects probed using Raman microscopy in JET limiter samples and beryllium-based synthesized samples.

We report on the detection by means of Raman spectroscopy amorphous beryllium deuteride, BeD 2 , in magnetron sputtered deposits synthesized two different laboratories and containing about 20 at.% deuterium. In contrast, this signature has not been found for JET limiter samples studied coming from inner, outer or upper limiters, even when a deposition zone limiters. give way to disentangle that other signatures falling same spectroscopic range mainly related phenomena. also analyze characteristics sample defects. These results could help interpretation D thermal desorption spectra future analyses thick Be deposit divertor tiles.