Laser-induced periodic alignment of Ag nanoparticles in soda-lime glass

Abstract

One-, two- or three-dimensional arrays of closely spaced silver nanoparticles may lead to new optical properties, due to short or long range coupling between their resonant surface plasmons, so that the spatially controlled growth of silver nanoparticles provides an efficient way to tune their optical properties. Towards this way, we present here the periodic pattern of a glass surface with silver nanoparticles by continuous ultraviolet laser exposure. The formation of the 160 nm period pattern is well described by an interference-based model which agrees with the experimental conclusions, mainly obtained by various forms of microscopy. Statistical approach based on the autocorrelation function gives quantitative description about the quality of the order in the periodic structure and about the nanoparticles averaged diameter (80 nm). We also present the optical extinction spectrum of the Laser Induced Periodic Surface Structure (LIPSS)-containing area of the glass, which unusually shows several bands in the visible range. The period of 160 nm of the periodic structure is short enough to allow coupling between nanoparticles, which makes it a possible candidate for plasmon-based optical applications.

Laser-Induced Periodic Surface Structures (LIPSS)

“…Early work was performed by Seifert et al (2005), who observed LSFL with periods ranging from 390 nm up to 1900 nm parallel to the polarization at the bottom of multi-pulse ablation craters in silver-doped soda-lime glass (λ = 400 nm, τ = 150 fs, ϕ 0 > 1 J/cm 2 , N < 500, f = 0.1 or 1 kHz, θ = 0 ). Goutaland et al (2013) reported the "self-ordered" alignment of Ag-NPs in HSFL of 160 nm period for the same material system under cw-UV-laser irradiation (λ = 244 nm, Ι 0~1 200 kW/cm 2 , 5 ms to 5 s exposure times, θ = 0 ). Liu et al (2017) have observed a larger variety of surface and bulk periodic structures consisting of Ag-NPs, arranged in orthogonal gratings with different periods and depths from the surface of a Ag/TiO 2 composite irradiated by fs-laser pulses (λ = 515 nm, τ = 370 fs, ϕ 0 = 0.029-0.062 J/cm 2 , N eff_1D = 165 or 1650, f = 500 kHz, θ = 0 ).…”

Third-order nonlinear optical vitreous material derived from mesoporous silica incorporated with Au nanoparticles

“…Laser irradiation, ion-exchange and laser directwriting methods in creating nanostructured particles inside glass merely form hundreds of micrometer surfaces containing polydispersed NPs. 14 Despite the success in preparing Au NPs stabilized in sol-gel-derived silica glass, 15 cracking may occur when the gel is dried and sintered. In addition, aggregation or coalescence of metal salts or NPs probably appears during solgel polymerization.…”

Towards a Glass New World: The Role of Ion-Exchange in Modern Technology

“…Besides the aforementioned thermal post-processes, other annealing techniques involve the use of continuous [102,[165][166][167] and/or pulsed lasers [98,101,[168][169][170][171] working at different wavelengths of the spectrum (from X-ray to ultraviolet (UV) and visible (VIS) regions up to infrared (IR) ones) and able to effectively reduce the noble metal ions in metal NPs. In this case, the mechanism of nanoparticle formation depends on the power of the laser source at the surface of the ion-exchanged specimen.…”

“…In this way, these metal nanostructures are ready for SERS sensing and no further etching step is required. If compared with the standard thermal annealing process in air, the one induced by laser irradiation is faster in terms of nanoparticle formation and offers the non-negligible advantage of being able to draw ordered structures of nanoparticles-equally spaced from each other-so that the SERS response of the substrate is enhanced [102,166]. Figure 6 sketches the mechanism of metal nanostructure formation by high power laser beam in the case of silver ion-exchanged glass (Figure 6a).…”