Optical properties of Ag nanocrystals in Sc and O sequentially implanted silica

Fabricating a Dichroic Plasmonic Mirror in Fused Silica by Dual-Ion Implantation

“…The nearly Gaussian depth profile has a peak approximately 140 nm below the surface that remains unchanged after oxygen implantation and after annealing. The implanted Ag follows a similar pattern, with a peak ∼130 nm below the surface [7]. The presence of Sc does not noticeably affect the depth of the Ag concentration peak but does broaden the distribution of implanted Ag.…”

“…This ultraviolet absorption has been attributed to the Sc 3+ chargetransfer band in silica, as well as to defects associated with the implantation process and the extrinsic doping effect of the Sc ions. Figure 2 shows that all samples exhibit strong absorption in the 400 to 430 nm range, which is characteristic of the localized surface plasmon resonance (LSPR) of silver in a silica matrix, and a shoulder on the red side of the LSPR peak frequently attributed to dipole-dipole interactions with neighboring NPs [5,7,15]. The 6 Ag sample shows a LSPR peak at 412 nm and a shoulder at ∼524 nm.…”

“…Infrared and optical spectra have shown that implanting Sc and O in silica, followed by annealing in oxygen at 900°C, produces a Sc-O-silicate phase that has only a small effect on the silica absorption spectrum [7]. Annealing at 900°C in oxygen removes most implantation-induced defects; however, due to the mismatch in bonding coordination between the Sc 3+ and Si 4+ ions, there may be defects associated with the presence of the Sc 3+ if the Sc ion replaces a Si ion in the silica network.…”

“…The samples were subsequently implanted with oxygen and annealed at 900°C for two hours to facilitate Sc incorporation into the silica network [1,7,11,14]. Ag was then implanted in the annealed samples, with ion-beam energies chosen so that implantation profiles overlapped with those of the Sc:O-implanted layer.…”

“…This increases the linear refractive index of the host and alters the short-and intermediate-range order (SRO and IRO) of the Sc-O-implanted silica matrix. This initial modification of the silica substrate by Sc and O implantation does not lead to phase separation, but does alter the size and depth distributions of the metal NPs as a function of Sc-ion dose [5,7,8].…”