Nanocomposites and nanomaterials

Core-shell nanostructures under localized plasmon resonance conditions
I. Yaremchuk1, T. Bulavinets1, V. Fitio1, Ya. Bobitski 1,2
1 Department of Photonics, Lviv Polytechnic National University,
S. Bandery str. 12, Lviv, 71013, Ukraine. 
E-mail: iryna.y.yaremchuk@lpnu.ua
2 Faculty of Mathematics and Natural Science, University of Rzeszów, 
Rejtan’s str. 16b, Rzeszów-35-959, Poland.

This work is devoted to the study and generalization of the physics of resonance phenomena that arise under interaction of the electromagnetic waves with core-shell nanostructures in conditions of localized plasmon resonances. The mathematical modeling of such phenomena for the search the structures parameters with a maximum manifestation of the resonance of the electromagnetic field with the next experimental confirmation is the basis for the development and manufacturing of various devices of the modern sensor electronics [1]. 
The spectral characteristics of the core-shell type nanostructures, namely silver-copper, silver-titanium dioxide, copper-cupric in the conditions of localized plasmon resonance have been theoretically studied for the purpose of their further photonics and plasmonics applications. It is shown that by changing the thickness of the shell on the metal or semiconductor core, one can shift the spectral position of the surface plasmon absorption peak in the visible spectral region and evaluate the influence of deformation of nanostructures on their optical characteristics. In the case of core-shell nanostructures there is a clearly pronounced additional peak in the spectra of absorption and scattering cross sections. Such a two-band nature can be explained by the excitation of localized plasmons on two interfaces metal/dielectric. The spectral position of the both peaks of absorption and scattering cross sections is shifted to the long-wave region of the spectrum, when the shell thickness changes and when the nanostructure is deformed (extended) for such type of the nanoshells.

Financial support of Ministry of Education and Science of Ukraine should be acknowledged (DB/Fotonika 0117U007176, DB/MEV 0118U000267)

1.	Gupta, B. D., Shrivastav, A. M., & Usha, S. P. (2017). Optical Sensors for Biomedical Diagnostics and Environmental Monitoring. CRC Press.