Neutron transmutation doping effect on the optical property of germanium nanocrystals

Arsenic-doped isotopic 74 Ge nanocrystals (nc- 74 Ge) embedded in amorphous SiO 2 films were prepared by neutron transmutation doping (NTD) and the influence of the As additive on the optical properties of the samples was investigated. The optical results showed that the original nc- 74 Ge photoluminescence (PL) (∼620 nm) blue-shift and PL quenching could be seen by the appearance of Auger-like recombination channels, while the increase in PL was produced by neutron irradiation and a second annealing, not by the As impurities.