Figure 6
From: Rare-earth metal catalysts for high-pressure synthesis of rare diamonds
Representative PL spectra of diamonds produced using heavy rare earth catalysts. The spectra were recorded at 80 K with excitation of 395 nm for diamonds synthesized in (a) Tm–C, (b) Tb–C, (c) Er–C and (d) Lu–C systems at 2000 °C. The spectra in each panel were normalized to show the same intensity of the diamond Raman peak and displaced vertically for clarity.
