Light-induced mass transport in amorphous chalcogenides/gold nanoparticles composites

Abstract

Abstract. We have established that mass-transport processes in two types of amorphous materials, based on light-sensitive inorganic compounds like Se and As 20 Se 80 chalcogenide glasses (ChG), can be enhanced at the nanoscale in the presence of localized plasmonic fields generated by visible light in gold nanoparticles (GNPs), if the condition of surface plasmon resonance (SPR) is fulfilled. It was found that irradiation by light in the presence of SPR produces profound surface nanostructurizations, and variation in topography follows closely and permanently the underlying near field intensity pattern. We have proposed a model of mass-transport in which the existence of moving anisotropic dipolar units and internal electric field in ChG as a main driving force of this movement is suggested.

Laser Recording in Chalcogenide Glass Films: Driving Forces and Kinetics of the Mass Transfer

“…The carriers move in a gradient of their concentration caused by inhomogeneous illumination. [ 23–27 ] Electric potential, which appears under inhomogeneous illumination of ChG films, was detected by Kelvin probe [ 24,26,28 ] that confirmed this driving force.…”

“…The carriers move in a gradient of their concentration caused by inhomogeneous illumination. [23][24][25][26][27] Electric potential, which appears under inhomogeneous illumination of ChG films, was detected by Kelvin probe [24,26,28] that confirmed this driving force. Under illumination by a focused beam, a lateral electric field is induced not only by a gradient of light intensity, but also by a temperature gradient, due to the Seebeck effect).…”

Rapid formation methods of arrays of randomly distributed Au and Ag nanoparticles, their morphologies and optical characteristics

“…2) the heater is a halogen lamp (12) with a power of 250 W and with mirror lens condenser (1), ( 2), (3). This condenser concentrate the radiation of the lamp on an aluminum plate (7), the underside of which is covered with heat-resistant blackening (5). A 0.8 mm diameter hole is made in the center of the plate (7), through which a small part of the light flux of the lamp (12) passes through the plate and the substrate (8) with the film (9) applied to it and enters the fiber optic input (11) of the Ocean Optics spectrophotometer.…”

“…Surface-Enhanced Raman Light Scattering (SERS) is an effective method for biological analysis molecules, living cells and substances in ultra-low concentrations, short-range structures of nanoscale chalcogenide films and its changes during annealing and laser irradiation, enhancement of photoinduced mass transport of matter in chalcogenide films, nanostructuring of their surfaces, etc. [1][2][3][4][5][6][7][8][9][10][11][12][13], because such arrays can lead to an increase in the electric field by several orders of magnitude due to the excitation of surface plasmon resonance (SPR).…”

“…Island-type films of noble metals are one of the most effective plasmon-active structures. In [5,6,9] it was shown that disordered Au NPs arrays can be formed by thermal annealing of thin nano-sized gold films in air, and the average size of nanoparticle and optical properties of arrays depend on the nominal thickness of gold films and annealing temperature. The rate of heating of metal films deposited on glass substrates also has a significant effect on the process of forming metal NPs arrays.…”