New ideally absorbing Au plasmonic nanostructures for biomedical applications

Abstract

In this paper a new set of plasmonic nanostructures operating at the conditions of an ideal absorption [1] was proposed for novel biomedical applications. We consider spherical x/Au nanoshells and Au/x/Au nanomatryoshkas, where 'x' changes from conventional Si and SiO 2 to alternative plasmonic materials [2], such as zinc oxide doped with aluminum, gallium and indium tin oxide. The absorption peak of proposed nanostructures lies within 700-1100nm wavelength region and corresponds to the maximal optical transparency of hemoglobin and melanin as well as to the radiation frequency of available pulsed medical lasers. It was shown that the ideal absorption takes place in a given wavelength region for Au coatings with thickness less than 12nm. In this case finite quantum size effects for metallic nanoshells play significant role. The mathematical model for the search of the ideal absorption conditions was modified by taking into account the finite quantum size effects.

Super-efficient laser hyperthermia of malignant cells with core-shell nanoparticles based on alternative plasmonic materials

“…These two configurations of nanoparticles attract significant attention since both of them exhibit strong surface plasmon resonances in near-IR. In this work, we limit the discussion to the core-shell spherical nanoparticles, however, along with SiO 2 /Au we consider AZO/Au configuration which has similar optical properties [21]. We describe the particle's geometry with two independent parameters: the total particle diameter d sh and the diameter of the core d c .…”

“…Usually, in PPTT, only absorbing properties of nanoparticles are taken into account. A number of researches have addressed the problem of optimizing the absorption efficiency of core-shell spherical nanoparticles [20,21]. However, when using short laser pulses in a real environment, high-gradient, fast-relaxing thermal fields appear, and the temperature of the cell membrane near heating nanoparticle will depend on a number of factors.…”

Thermoelectric and Plasmonic Properties of Metal Nanoparticles Linked by Conductive Molecular Bridges

“…[1,2,[15][16][17][18][19] The reason for that is the strong dependence of the electromagnetic field strength, generated by LSPs, on distance and interaction between NPs. Therefore, there are a variety of different forms of plasmonic materials, such as individual NPs of different shapes and materials [20] and 2D lattices. [11][12][13]21] A presence of conductive material between two NPs leads to the emergence of a new mode, called the charge transfer plasmon (CTP), where the charge periodically moves between two NPs along a conductive bridge.…”

Electromagnetic energy in multilayered spherical particles

“…The solution of this problem implies the definition of the electromagnetic field within or outside of a sphere which allows to get its absorption, scattering, extinction or other important characteristics. Among these properties, the cycle-and orientation-averaged electric |E| 2 and magnetic |H| 2 fields (in general, electromagnetic energy) within a particular layer (shell) or in the vicinity of a multilayered sphere is of great importance since it defines performance and suitability of a multilayered sphere for a large number of intriguing applications: nonlinear optics [17][18][19], lasing [20][21][22], heating [23][24][25], photocatalysis [26], fluorescence enhancement [27][28][29][30], plasmon-enhanced upconversion [31,32], energy harvesting and storing [33][34][35][36], surface-enhanced Raman spectroscopy [37][38][39], biology and medicine [40][41][42][43][44].…”