Confinement effect and low-defect density-induced long lifetime Er silicate nanowire embedded in silicon oxide film

Abstract

In this study, we have developed a reduced Er-Er interaction strategy for pursuing long lifetime and high efficiency luminescence in Er compounds with higher Er concentration. Annealing temperature and atmosphere dependence of the optical properties from Er silicate nanowires embedded in silicon oxide films have been investigated. The record long lifetime α-Er2Si2O7 of 844 µs is achieved through simultaneously reducing defect density and Er-Er interaction. The low-defect density in the α-Er2Si2O7 nanowires is mainly attributed to following aspects: no hydroxyl groups contamination, effective surface passivation and saturation of oxygen vacancies. The interaction of Er-Er ions is confined by the alteration of phonon density of states effects in the α-Er2Si2O7 nanowires. More significantly, the up-conversion emissions in the α-Er2Si2O7 nanowires also reduce effectively because of the nanoconfinement effect.