Electron beam controlled restructuring of luminescence centers in polycrystalline diamond

Color centers in diamond are becoming prime candidates for applications in photonics and sensing. In this work we study the time evolution of cathodoluminescence (CL) emissions from color centers in a polycrystalline diamond film under electron irradiation. We demonstrate room-temperature activation of several luminescence centers through a thermal mechanism that is catalyzed by an electron beam. CL activation kinetics were measured in realtime and are discussed in the context of electron induced dehydrogenation of nitrogen-vacancy-hydrogen clusters and dislocation defects. Our results also show that (unintentional) electron beam induced chemical etching can take place during CL analysis of diamond. The etching is caused by residual H2O molecules present in high vacuum CL systems.