Richard Tarparelli

Surface plasmon resonance of nanoshell particles with PMMA-graphene core

Purpose – The purpose of this paper is to contribute an analytical and numerical study of a new type of nanoshell particles operating in the visible regime. Design/methodology/approach – The structure consists of a core/shell particle, arranged in a planar array configuration, with a polymethyl methacrylate (PMMA)-graphene core and gold thin shell. Findings – By exploiting the proposed analytical model the design of a metamaterial-based sensor, operating in the optical frequency range, for the detection of tissue diseases is shown. Originality/value – Full-wave simulations confirm the capability of the proposed sensor to identify different compounds by refractive index measurement.

Spectral Green's Function for SPR Meta-Structures

In this paper we propose a new approach to study the electromagnetic field in Surface Plasmon Resonance (SPR) meta-structures. The geometry is a planar structure infinitely extended with a pulse excitation current embedded in the substrate. The general solution has been applied to a specific geometry that is frequently employed to model practical problems. The minimization of the thickness changes spectral Greens function in a more efficient form, suitable for calculations. Plasmon electric field expression on interface plane is obtained. This kind of meta-structures is suitable in various fields of application (e.g. optoelectronics and electromagnetic sensors).

Graphene Bow-tie Nanoantenna for Wireless Communications in the Terahertz Band

The interconnection of nanoscale devices (i.e., nanonodes) within a nanonetwork with existing communication networks, as well as the Internet, defines a new networking paradigm, namely the Internet of Nano-Things. Within this context, the definition of a nanonode requires specific features, especially for what concerns novel nanomaterial and components. Graphene-enabled wireless communications is emerging as a novel paradigm, which has been proposed to implement wireless communications among nanosystems. Indeed, graphene-based plasmonic nanoantennas, namely graphennas, are just a few micrometers in size, and are accordingly tuned to radiate electromagnetic waves in the terahertz band. In this work, the important role of the graphene conductivity in the contest of the characteristics of graphene-based nanoantennas is analyzed. Basically, we propose a particular shape for a nanoantenna (i.e., a bow-tie nanoantenna), and we study its radiation performance both in transmission, and reception. The resonance frequency of this kind of antenna is achieved by full-wave simulation. Moreover, the influence of the geometrical parameters is also evaluated. Numerical results will prove useful for designers of future graphene-based antennas, which are estimated to enable wireless communications in nanosystems.

Electromagnetic analysis of deep brain stimulation

In this contribution the stimulus complications in DBS (Deep Brain Stimulation) are evaluated and discussed. In particular we present a new method to predict the network response when a DBS stimulus is applied. A neural network similarly to ipsi-contralateral nerve topology is presented. The network consists of 175 neurons arranged in three layers. To validate the DBS stimulus propagation extensive numerical analyses have been conducted through Neuron software simulations. Results confirm the possibility to predict the correct stimulation parameters.

Multi resonant platform based on modified metallic nanoparticles for biological tissue characterization

In this contribution optical properties of new metallic nanoparticles for biomedical applications are investigated. These particles consist of a pair of opposing gold prisms with asymmetric dielectric holes. In this configuration the structure exhibits multi-resonant behavior in the Visible and Near Infrared Region, useful tool for multi-sensing platform based on local refractive index measurements. The electromagnetic properties of the structure are evaluated in terms of extinction cross-section through proper full-wave simulations. The sensitivity performances for the local refractive index variation are discussed. The obtained results show that the proposed particles could be efficiently applied for sensing applications.

Electromagnetic Nanonetworks for Sensing and Drug Delivery

The use of nanodevices for biomedical applications has recently been object of study by researchers. Novel prospectives can be envisaged in the field of nanomedicine, also supported by innovative nanodevices with specific properties. In this chapter, we present the electromagnetic properties of different metal nanoparticles (i.e., nanocube, nanocylinder, nanorod, bow-tie, biconical nanoparticle, etc.), opportunely functionalized for sensing applications, as well as drugged with medicament to be released to specific locations, for innovative therapeutic treatments. After modeling the design of such nanoparticles, we investigate the channel model adopted in electromagnetic nanonetworks. Basically, we focus on the nanoparticle transmission, diffusion and reception processes, both for extra- and in-vivo applications i.e., for the detection of target cells in a biological tissue sample, and for drug delivery via nanoparticle adsorption, respectively. Numerical results obtained through full-wave simulations have shown the effectiveness of electromagnetic nanoparticles for specific biomedical applications (e.g., DNA alteration detection). Finally, we highlight that in this chapter the electromagnetic properties that are described are used for sensing and drug delivery, and not for communication among nanoparticles.

Metamaterial-based sensor for skin disease diagnostics

Skin absorption properties, under diseases conditions, are modified due to the structural variations of chromophores and pigments. The measurement of such different absorptions can be a useful tool for the recognition of different skin diseases. In this study the design of a multi-resonant metamaterial-based sensor operating in the optical frequency range is presented. The sensor has been designed, in order to have multiple specific resonant frequencies, tuned to the skin components spectral characteristics. A change in the frequency amplitude of the sensor response is related to the different absorption rate of skin chromophores and pigments. A new analytical model, describing the multi-resonant sensor behaviour, is developed. Good agreement among analytical and numerical results was achieved. Full-wave simulations have validated the capability of the proposed sensor to identify different skin diseases.