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8LM-PS-5
Study of the dynamics of plasmon resonance conditions at the water-film Ag interface
M. Kononov1, V. Pustovoy2, V. Svetikov1
1Prokhorov General Physics Institute of the Russian Academy of Sciences, laser phisics, Moscow, Russian Federation
2Prokhorov General Physics Institute of the Russian Academy of Sciences, Laser Physics, Moscow, Russian Federation
In this work, we studied the conditions for the excitation of surface plasmon resonance (SPR) at the interface of a silver film-deionized water. The interaction of water with metals is of interest to scientific groups working in various branches of science and engaged in the creation of sensory systems.
The particular interest is the mechanism of interaction of dipoles of water molecules with a metal surface, which characterizes the adsorption interaction. The relevance of this topic is largely due to the demand for optical sensor devices in biology and medicine.
We used the method of SPR excitation on a glass prism in according to the Krechman geometry in our studies. The experiments were conducted in the scheme of a closed cell with a constant flow of water. A feature of this scheme is the lack of contact of the metal surface with air. The main detection element is the prism with a refractive index of n = 1.75, has been covered by a silver film with a thickness of 54 nm on the hypotenuse surface [1,2].
We investigated the dynamics of changes of the SPR conditions on the time without changing (updating) the aquatic environment. It was shown that the plasmon resonance conditions at the metal-water interface does not remain stationary, but varies monotonically on time. Such behavior of resonance conditions is associated with a change in the density of the electronic states of a metal surface. This leads to a change in the distribution density of water molecules on the surface with the formation of an ordered structure that repeats the crystallographic symmetry of the metal.
References
[1] Plasmonic spectroscopy of the water solutions of the copper phthalocyanine adsorbed on silver surface// Proceedings of the 2018 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering, ElConRus 2018 2018. p. 1989-1991.
[2] Vinogradov S.V.,Kononov M.A.,Pustovoi V.I.,Svetikov V.V. Plasmonic spectroscopy of the water solutions of the copper phthalocyanine adsorbed on a silver surface //Appl. Phys. 2017. Vol. 1. p. 6973.
