Modification of the optical properties of Ag-implanted silica by annealing in two different atmospheres

Abstract

Significant changes in the optical properties of nanometer-size Ag clusters embedded in high-purity silica were obtained. Samples were prepared by 2 MeV Ag-ion implantation with fluences in the 2.8–3.8×1016 ions/cm2 range and subsequent annealing at various temperatures in air (oxidizing atmosphere) or in a hydrogen-rich atmosphere (reducing atmosphere). Changes consisted of large and small blueshifts of the resonance surface plasmon peak position, light absorption modification in the ultraviolet (UV) region, increased optical extinction in all the spectrum wavelength range, and different resonance peak height depending on annealing atmosphere. Optical property changes were analyzed in terms of Ag cluster size, interaction at cluster–matrix interface, cluster hydrogen content, diffusivity and conductivity. Bands in the UV region are reported.

Enhancement and quenching of photoluminescence from silicon quantum dots by silver nanoparticles in a totally integrated configuration

“…(2), the mean size of the Ag NPs was 3.11 nm, 3.42 nm and 3.38 nm for the samples implanted at 1 MeV, 2 MeV and 3 MeV, respectively. From our previous works 25,26 in the case of low fluences of Ag ions, i.e. when smaller Ag NPs are formed, no plasmon absorption band was observed, and the samples must then exhibit an absorption band in the UV region between 200 nm and 300 nm (centered around 250 nm), which corresponds to the interband transitions in Ag NPs smaller in size than 2 nm.…”

“…[23][24][25] According to Eq. (2), the mean size of the Ag NPs was 3.11 nm, 3.42 nm and 3.38 nm for the samples implanted at 1 MeV, 2 MeV and 3 MeV, respectively.…”

Optical properties of ZnS:Mn nanocrystals

“…Article defects in silica are the B 2 centers with absorption line around 5 eV and the E' centers with absorption line around 5.8 eV [9][10][11]. Although most of them are located in the ultraviolet, the transitions linked to these defects could have the direct consequences on the visible spectrum.…”

Optical characterization of thermally annealed self‐assembled ZnCdSe quantum dots

“…Up to now, several TA studies have been performed with quantum dots (QDs) and quantum wells (QWs). It has been demonstrated that by varying the temperature (T A ) or the time (t A ) during TA, the emission from low dimensional semiconductors, can be significantly enhanced and tuned over a wide range of wavelengths, due to an interdiffusion of atoms between the barrier and the quantum well or the quantum dot [1][2][3]. Interestingly, it is also possible to reduce the dimension of a semiconductor, locally, by means of TA.…”