Broadband luminescence of Cu nanoparticles fabricated in SiO₂ by ion implantation

In this study, we investigate optical properties of metal nanoparticle crystals fabricated by implanting copper (Cu) ions into single silica (SiO₂) crystals with 400 keV at various ion doses. The Cu implanted SiO₂ (SiO₂:Cu) crystal produces a broadband luminescence emission, ranging from blue to yellow, and having a blue luminescence peak at 546 nm. Such anomalous luminescence emission bands suggest that the ion implantation may give rise to aggregation of Cu nanoparticles in the host matrix. The boundary element method-based modelling of a given Cu nanoparticle aggregation was employed to justify the broadband luminescence emission. Formation of Cu nanoparticles in SiO₂ is predicted through their optical absorption data. The experimental results are compared with results of Mie calculations and we observe that the higher ion dose produces the larger particle size. - Highlights: • We present the fabrication of metal nanoparticle crystals by implanting Cu into SiO₂. • Numerical modelling of the Cu nanoparticles was employed. • Mie theory and BE method for a cluster of closely packed nanoparticles were used.