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In this work, we propose the synthesis of ZnO nanostructures through the thermal oxidation of ball-milled powders with the introduction of Mg and Sn doping species at the preliminary step of milling. We investigate the advantages and challenges of this two steps process for the production and fabrication of highly crystalline ZnO nanowires. This simple method allows us to fabricate ZnO nanowires with a higher quality core crystal at a much lower temperature and for a shorter processing time than the state-of-the-art, and decorated with by ZnO2 nanoparticles as determined via TEM analysis. The main findings will show that the crystalline core of the nanowires is of hexagonal ZnO while the nanoparticles on the surface are ZnO2 cubic type. Generally, the method proves to be suitable for applications that require a high surface-to-volume ratio, for example, catalysis phenomena, in which the presence of zinc oxides species can play an important role.

In this article, the low-frequency magnetic shielding effectiveness of a planar screen with magnetic and conductive properties in a coplanar-loops configuration (as required in the IEEE Standard 299) is evaluated through a new closed-form formula under the thin-sheet and small-loop approximations. The formulation clearly shows the separate contribution of the permeability and the conductivity of the screen to the shielding performance. The results obtained with the proposed closed-form formulas are compared with the exact ones derived through numerical integrations to assess the relevant accuracy and limits of validity.

A recent analytical formulation for the low-frequency magnetic shielding effectiveness of a thin metal screen against a circular loop source is extended to the case of a screen exhibiting both magnetic and conductive properties. The presence of magnetic properties introduces a series impedance in the equivalent network of the structure, in addition to the shunt admittance associated with the screen conductivity. However, the fields scattered by the two elements do not interact and hence can be treated independently; furthermore, the series impedance gives rise to integrals akin to those stemming from the shunt admittance. A generalized analytical formulation for a combined magnetic and conductive screen is thus obtained, that is favorably compared with both classical approximate formulations and exact results.

The dispersive properties of the first higher order (EH $_1$ ) mode in uniform graphene nanoribbons over a ground plane are numerically studied to point out the characteristics of the bound-mode and leaky-mode regimes. The graphene nanoribbon is then suitably designed to operate on the EH $_1$ mode as a frequency-scannable leaky-wave antenna in both the millimeter and terahertz ranges.

The 3-D time-domain Green’s function (GF) for the vector potential excited by a transient vertical electric dipole in the presence of a thin sheet with high-contrast dielectric and conductive properties is derived using a modified Cagniard–de Hoop approach. The resulting expression involves the numerical evaluation of a 2-D integral over a finite integration domain, computationally much less expensive than the direct numerical evaluation of the inverse Laplace/Hankel transform of the relevant spectral-domain GF. Expressions for the transient electromagnetic fields can thus be obtained, and numerical results are provided, which illustrate their salient features and validate the proposed formulation.

We investigated 30 kV Ga+ ions treatments on (0001) single crystal ZnO in order to assess the potentiality of ion beam based device fabrication on such material. A multi-technique approach combining atomic force microscopy, Raman and energy dispersive X-Ray spectroscopies, and transmission electron microscopy was used to study morphological and structural properties of ZnO upon varying the ion dose. At low doses a shallow defective layer develops showing an increasing defect density as the dose is increased. At higher dose a thinner defective layer with an amorphous layer on top is produced. The ion beam damaged layer on high resistivity ZnO shows enhanced conductivity. KOH based etching removed selectively the damaged ZnO and was found to dissolve rapidly the Ga-rich amorphous layer. The defective layer has an etch rate which depends on the ion dose, and even for prolonged etching processes it was not completely removed. However, conductivity measurements on ion beam fabricated pillars showed that the residual defects do not give a detectable electrical response. These findings indicate that electronic devices and micro-structures with pristine electrical properties of the ZnO crystal can be reliably fabricated by focused ion beam, provided the damaged surface layer is removed by proper etching procedures. Keywords: Zinc oxide, Focused ion beam, Raman spectroscopy, Transmission electron microscopy, Defects

Due to its piezoelectric and semiconductive properties, ZnO is actively investigated for the development of innovative nanostructures for applications ranging from piezotronics to energy harvesting. In the present paper we develop a full model for the non-linear piezoelectricity in ZnO nanowires, where both direct and inverse non-linear piezoelectric effects are accounted for. The preliminary results show for the first time the importance of non-linear effects on the electro-mechanic behavior of nanowires especially when used for piezotronic applications.

Nanofibers produced by electrospinning show an interlaced and highly porous structure with a large surface-to-volume ratio. Such property makes the nanofibers useful in several applications such as healthcare, biotechnology, environmental engineering, defense & security, and energy storage. In this study polycaprolactone nanofibers have been tested as a mock-up separator in a lithium metal battery to evaluate the ion transport properties of ultrafine electrospun materials and assess the potential of this fabrication technology for lithium batteries. The membranes were soaked with an electrolyte solution and characterized by electrochemical impedance spectroscopy, finding that the porous structure of the polycaprolactone nanofiber membrane favors a complete and rapid uptake of the electrolyte. Furthermore, the large surface area of the nanofibrous network enhances ion conductivity, improving the power response of the polymer battery as compared with other polymer batteries. The electrochemical performance of a full battery was obtained on a prototype battery assembled by sandwiching the electrolyte-soaked nanofibrous membrane between a lithium anode and a LiFePO4 based cathode. The results showed that the battery can be discharged at high power with a good capacity retention. Despite intrinsic limitation of the polycaprolactone per se, the good performance of these membranes as separator certainly indicates that electrospinning is a relevant candidate method to develop and produce separators for high power batteries.

In this article, we propose the fabrication of ZnO nanostructures through the thermal oxidation of ball-milled doped powders. We investigate the applications, advantages, and challenges of this two steps process for the production and fabrication of high-quality and high-performance nanowires to be used in a large variety of applications.

ZnO-based nanomaterials are a subject of increasing interest within current research, because of their multifunctional properties, such as piezoelectricity, semi-conductivity, ultraviolet absorption, optical transparency, and photoluminescence, as well as their low toxicity, biodegradability, low cost, and versatility in achieving diverse shapes. Among the numerous fields of application, the use of nanostructured ZnO is increasingly widespread also in the biomedical and healthcare sectors, thanks to its antiseptic and antibacterial properties, role as a promoter in tissue regeneration, selectivity for specific cell lines, and drug delivery function, as well as its electrochemical and optical properties, which make it a good candidate for biomedical applications. Because of its growing use, understanding the toxicity of ZnO nanomaterials and their interaction with biological systems is crucial for manufacturing relevant engineering materials. In the last few years, ZnO nanostructures were also used to functionalize polymer matrices to produce hybrid composite materials with new properties. Among the numerous manufacturing methods, electrospinning is becoming a mainstream technique for the production of scaffolds and mats made of polymeric and metal-oxide nanofibers. In this review, we focus on toxicological aspects and recent developments in the use of ZnO-based nanomaterials for biomedical, healthcare, and sustainability applications, either alone or loaded inside polymeric matrices to make electrospun composite nanomaterials. Bibliographic data were compared and analyzed with the aim of giving homogeneity to the results and highlighting reference trends useful for obtaining a fresh perspective about the toxicity of ZnO nanostructures and their underlying mechanisms for the materials and engineering community.

With the aim of tuning the optical properties of SiC selective solar absorbers, we investigate the surface micro/nano-texturing of porous silicon carbide by using two approaches, namely i) the femtosecond laser treatment and ii) the fluorine based reactive ion etching. It is found that both the techniques are capable of inducing significant surface morphology modification inducing a substantial roughening. The surface features produced are found to be tunable by tailoring the main process parameters, i.e. translation speed and pulse repetition rate for laser treatment, and RF-power, gas pressure and gas mixture for the reactive ion etching process.

The development of smart and intelligent regenerative biomaterials for skeletal muscle tissue engineering is an ongoing challenge, owing to the requirement of achieving biomimetic systems able to communicate biological signals and thus promote optimal tissue regeneration. Electrospinning is a well-known technique to produce fibers that mimic the three dimensional microstructural arrangements, down to nanoscale and the properties of the extracellular matrix fibers. Natural and synthetic polymers are used in the electrospinning process; moreover, a blend of them provides composite materials that have demonstrated the potential advantage of supporting cell function and adhesion. Recently, the decellularized extracellular matrix (dECM), which is the noncellular component of tissue that retains relevant biological cues for cells, has been evaluated as a starting biomaterial to realize composite electrospun constructs. The properties of the electrospun systems can be further improved with innovative procedures of functionalization with biomolecules. Among the various approaches, great attention is devoted to the “click” concept in constructing a bioactive system, due to the modularity, orthogonality, and simplicity features of the “click” reactions. In this paper, we first provide an overview of current approaches that can be used to obtain biofunctional composite electrospun biomaterials. Finally, we propose a design of composite electrospun biomaterials suitable for skeletal muscle tissue regeneration.

The transient electromagnetic field transmitted by a pulsed horizontal electrical dipole through a planar conductive screen with finite thickness is numerically evaluated through the efficient evaluation of classical Sommerfeld integrals and inverse Fourier transform techniques. The proposed numerical approach allows for accurately evaluating the relevant time-domain shielding characteristics.

The preformance of finite size planar shields usually adopted in EMC practice against near field extremely low-frequency magnetic sources magnetic sources are here investigated. The analysis is performed numerically with frequency-domain techniques and it is aimed at assessing the influence of shield constitutive parameters and of the source distance on the shielding parameters.

The shielding effectiveness of a planar multilayered screen is computed in the time domain in the presence of near-field magnetic sources. The proposed numerical method involves the efficient evaluation of classical Sommerfeld integrals and the inverse-Fourier transform through double-exponential formulas. For sufficiently thin screens with highly-conductive properties, an analytical method, based on a modified Cagniard-de Hoop approach, is also presented to validate the results.

The magnetic shielding effectiveness of finite-width thick planar screens against near-field sources producing extremely low-frequency magnetic fields is studied in detail. In particular, by means of a careful numerical analysis, the effects of several screen parameters (such as dimensions, constitutive parameters, and position with respect to the source) are accurately assessed, in addition to shedding light into the main field penetration mechanisms.

In high voltage transmission lines, shield wires are periodically grounded and can be periodically sectionalized for several purposes. These two practices have important effects on multiconductor transmission lines, since both affect the wave propagation along the line. In this work, the attention is focused on the frequency behavior of the characteristic impedance. Moreover, the effect of wires transposition on the characteristic impedance is also investigated.

We report on the conductive-atomic force microscopy (C-AFM) study of metallic layers in order to find the most suitable configuration for electrical characterization of individual ZnO micro-pillars fabricated by focused ion beam (FIB). The electrical resistance between the probe tip and both as deposited and FIB processed metal layers (namely, Cr, Ti, Au and Al) has been investigated. Both chromium and titanium evidenced a non homogenous and non ohmic behaviour, non negligible scanning probe induced anodic oxidation associated to electrical measurements, and after FIB milling they exhibited significantly higher tip-sample resistance. Aluminium had generally a more apparent non conductive behaviour. Conversely, gold films showed very good tip-sample conduction properties being less sensitive to FIB processing than the other investigated metals. We found that a reliable C-AFM electrical characterization of ZnO microstructures obtained by FIB machining is feasible by using a combination of metal films as top contact layer. An Au/Ti bilayer on top of ZnO was capable to sustain the FIB fabrication process and to form a suitable ohmic contact to the semiconductor, allowing for reliable C-AFM measurement. To validate the consistency of this approach, we measured the resistance of ZnO micropillars finding a linear dependence on the pillar height, as expected for an ohmic conductor, and evaluated the resistivity of the material. This procedure has the potential to be downscaled to nanometer size structures by a proper choice of metal films type and thickness. (C) 2016 Elsevier B.V. All rights reserved.

Nano-scale devices based on zinc oxide (ZnO) are expected to be widely used as building-blocks of future innovative sensors due to outstanding properties of this semiconductive material including presence of a direct bandgap, piezoelectricity, pyroelectricity, biocompatibility. Zinc oxide nanostructures can be also conceived as ultra-high efficiency nanogenerators to harvest electrical energy from the strain vibrational energy in order to drive an array of nanosensors. In fact most applications are based on the cooperative and average response of a large number of ZnO elongated micro/nanostructures, such as wires, rods and pillars. In order to assess the quality of the materials and their performance it is fundamental to characterize and then accurately model the specific electrical and piezoelectric properties of single ZnO structures, in an integrated manner. In this paper, we report on the brittle-to-ductile transition that occurs when reducing the size down to the nanoscale, which has been rarely documented. Then we report on focused ion beam machined of high aspect ratio nanowires and pillars and their mechanical and electrical (by means of conductive atomic force microscopy) characterization. Finally, we present new simulation results concerning ZnO nanowires under lateral bending obtained through the classical approach and the finite element method. Here we use a new power-law design concepts to accurately model the relevant electrical and mechanical size-effects whose existence has been emphasized in recent reviews. (C) 2016 Elsevier B.V. All rights reserved.

Propagation and attenuation properties of modes supported by graphene nano-ribbons placed on top of a grounded dielectric substrate are investigated by means of a spectral-domain Method-of-Moments approach together with a dyadic description of the graphene conductivity obtained based on semiclassical and quantum-mechanical arguments. Such a description takes into account the possible presence of static biasing fields or spatial-dispersion effects. The attenuation features are investigated and are compared to those of similar metal structures.

ZnO is receiving a considerable attention for the development of novel cost-effective nanostructures with outstanding functional properties for applications in electronics and energy. In this paper, we investigate the effects of the nonlinear piezoelectricity, that has been recently observed in ZnO nanostructures, on the piezotronic effect of ZnO nanowires (NWs). We insert a physically-based model of the nonlinear direct piezoelectric effect into a fully-coupled thermo-mechanical-electric scheme to study the current-voltage characteristic of ZnO NWs under a purely vertical compressive/tensile strain. Our results show for the first time that the nonlinear piezoelectricity deeply affects the current transport processes inside the NW and the behavior of devices for piezoelectric-piezotronic applications and provides remarkable insights into the underlying physics. © 2002-2012 IEEE.

Dispersion properties of the dominant modes supported by different 2-D graphene-based nanowaveguides are studied by means of an exact approach based on the transverse-resonance technique and using an equivalent-circuit representation of graphene sheets which also takes into account the spatially dispersive nature of the graphene conductivity: it is quantitatively shown that neglecting spatial-dispersion effects can cause errors in the determination of the modal properties of extremely slow surface waves, also well below the terahertz regime. The modal features of graphene nanowaveguides are thus investigated in detail showing their potential in future nanoelectromagnetic and nanophotonic applications.

ZnO is receiving a considerable attention for the development of novel cost-effective one-dimensional nanostructures with outstanding functional properties for applications in electronics and energy. We propose a fully-coupled thermo-mechanical-electric scheme to study the current-voltage characteristic of piezoelectric ZnO NWs under a purely vertical compressive/tensile strain. Our results confirm that the thermal transport processes deeply affect the behavior of devices for piezoelectric-piezotronic applications and provides remarkable insights into the underlying physics. © 2015 IEEE.

A novel Frequency Selective Surface (FSS) is proposed for the design of polarization-insensitive metamaterial absorbers that operate around 1 GHz, where the first resonances of small commercial enclosures take place. The novel FSS is based on the simplification of an alternative Roman maze. It shows a strong sub-wavelength response and is promising for the design of compact planar absorbers with excellent angular and polarization stability.

Zinc oxide structures with size in the micro and nano-scale range represent key candidates for developing novel, cheap and efficient electronic devices, power generators and sensors based on the cooperative response of a large number of synced structures. The accurate electrical characterization of single ZnO micro/nanostructures is thus critical for assessing and optimizing the device performance and reliability, and requires the use of metallic scanning nano-probes for establishing electrical contact with the nano-structures. We report on the characterization of the contact resistance between AFM conductive tip and a selection of metallic layers to be used as top metallic coating allowing for nano-electrical characterization of FIB machined ZnO micro/nanopillars. Our findings show that the use of an Au film on top of Ti ohmic contact layer is crucial for reliable conductive AFM investigation of single isolated ZnO micro and nano-structures. © 2015 IEEE.

Zinc Oxide (ZnO) nanoscale nanowires (NW) and pillars exhibit substantial size-effects in mechanical properties as a function of diameter D, which enables their exploitation for nanotechnology purposes. Both elastic (i.e. the Young's Modulus, E) and fracture properties of ZnO nanostructures are key and need to be characterized for the sake of designing MEMS and NEMS, such as nanogenerators based on NWs. Both size-effects in inelastic and inelastic properties were described by distinct power-laws, although less attention has gone to showing another important property in failure mode, which shift from brittle in bulk ZnO to ductile in ZnO nanoscale samples. This aspect is very important as it reinforce the concept of damage tolerance of an otherwise brittle materials system and could enable new fabrication route of MEMS/NEMS by plastic deformation. We report preliminary observations from controlled microcompression tests on pillars of unprecedented small size, with an emphasis on strategy and equipment used to perform such accurate miniaturized nanomechanical tests. © 2015 IEEE.

Fundamental properties of plasmon modes propagating along graphene nanoribbons are investigated by means of a Method-of-Moments approach together with a dyadic description of a nonlocal graphene conductivity. Modal propagation, field distributions, and characteristic impedances are studied in details showing the dramatic effects of spatial dispersion.

Fundamental properties of surface plasmon polariton modes propagating along graphene nanoribbons are investigated by means of a full-wave method-of-moments approach adopting a spatially dispersive dyadic model for graphene conductivity. Modal propagation, current profiles, field distributions, and characteristic impedances are studied in detail showing the dramatic effects of spatial dispersion and the need to go beyond the usual weak (low- $q$ ) spatial dispersion formulation.

The design and the finite-element analysis of a novel microstrip antenna suitable for low-frequency applications is presented. The patch is mounted on a double-layered substrate of ferroelectric and ferrimagnetic materials to lower the resonant frequencies. The media are accurately simulated, accounting, respectively, for their frequency-dependent and anisotropic behavior.

Dispersion, attenuation and characteristic impedance of the fundamental modes supported by a pair of identical graphene nanoribbons in free space are studied. An efficient full-wave approach is adopted, based on a method-of-moments discretization of the relevant electric-field integral equation in which the graphene is modeled through a simple local conductivity. A spatial-domain formulation is adopted as it allows for efficiently treating nanoribbons with wide transverse separations and having in mind future treatment of spatially nonuniform graphene conductivities.

Zinc Oxide piezoelectric nanowires may offer unprecedented functional properties for piezotronics and piezoelectrics due to their electrical properties combined to the increased strength. Conventional "bulk" modeling used so far has suggested that "the smaller, the better" is the design tenet to obtain stronger and more reliable systems with higher piezopotential and efficacy. However, prior work has never addressed the interaction between electrical and mechanical size-effects of ZnO NWs, particularly the effect of the mechanical stiffening on the piezoelectric potentials and mechanical-to-electrical conversion efficacy of a NW. In this paper we propose a refined "size-dependent" modeling based on a "double power-law scaling" for the mechanical size-effects, which reveals, though consistent simulations based on the Finite Element Method, that stiffening effects can indeed collide with the electrical size-effects in very small NWs, thus meaning that minimizing the NW diameter does not yield always the best piezo-performance, as purported by standard bulk modeling. Our computations support that the elastic size-effects need to be carefully accounted in the design of ZnO NWs piezo-technology. © 2014 AIP Publishing LLC.

In this work we report on hydrothermal growth of ZnO nanostructures obtained by using strip-shaped resist templates made by electron beam lithography, with particular focus on: (i) the effects of materials used and processing on the template adhesion and its stability during wet growth; (ii) the influence of the template pattern dimensions on the nanowires morphology. Templates made of patterned films with methylmethacrylate-methacrylic acid copolymer showed greater adhesion and stability with respect to the commonly used poly (methylmethacrylate) electron resist or to the use of thin adhesion-promoter photoresist layers. The growth of nanowires in strip-shaped methyl methacrylate-methacrylic acid copolymer templates has been investigated using typical hydrothermal growth parameters and a marked dependence of nanowires length and diameter has been found on the template size for strips narrower than about 2 ?m. © 2014 Elsevier B.V. All rights reserved.

The charge transport in zinc-oxide piezosemiconductive nanowires under purely vertical compressive or tensile strains is investigated. For simplicity, only the additional band bending originated by the piezoelectric charges has been accounted for. Moreover, a constant volumetric piezoelectric charge density is assumed, distributed within a maximum distance $\delta_{\rm piezo}$ from the two junctions between the metal ends and the nanowire. Examples demonstrate that the carrier concentration, the energy conduction band profile, and the current–voltage characteristics significantly depend on $\delta_{\rm piezo}$. Therefore, we propose the use of current–voltage measurements to obtain information on $\delta_{\rm piezo}$ in strained piezosemiconductors.

The possibility of achieving directive fan-beam radiation with planar Fabry-Pérot cavity antennas constituted by an upper ferroelectric thin film and a lower ground plane having ultrasubwavelength thickness is studied by means of a simple transverse-equivalent-network approach and a cylindrical leakywave analysis, deriving simple design formulas. The performance of the proposed antenna is investigated in terms of power density radiated at broadside and directivity in the principal planes, pointing out the main limitations and tradeoffs associated with the reduced thickness.

The piezoelectric performance of ultra-strength ZnO nanowires (NWs) depends on the subtle interplay between electrical and mechanical size-effects. "Size-dependent" modeling of compressed NWs illustrates why experimentally observed mechanical stiffening can indeed collide with electrical size-effects when the size shrinks, thereby lowering the actual piezoelectric function from bulk estimates. "Smaller" is not necessarily "better" in nanotechnology. (Figure Presented).

A novel Frequency Selective Surface (FSS) conflguration is proposed for the design of polarization-insensitive metamaterial absorbers operating below 1GHz, where the flrst resonances of small commercial enclosures appear. The novel FSS shows a strong sub- wavelength response, enhanced by the dielectric substrate, which allows the design of compact planar absorbers with excellent angular and polarization stability.

Here we study the piezopotential, the carrier concentration, and the stored energies in laterally bent piezo-semiconductive NWs with total-bottom contact. Moreover, we give reasons for the well-known existence of two regions where the piezopotential has an opposite sign in comparison with the rest of the NW. Finally, we provide an upper limit to the static mechanicalto-electrical conversion efficiency by computing the ratio between the total stored electrostatic energy and the total (mechanical and electrostatic) stored energy. Our results can provide guidelines for designing devices based on laterally bent piezoelectric NWs.

Conical nanowires appear to be very versatile nanostructures for fabricating high performance piezoelectric nanodevices, for possible applications in the fields of mechanical sensing, piezotronics or piezo-photo-tronics. The results discussed in the present work are aimed at providing useful guidelines for the design of such devices.

We investigate the electrical transport in quasi-1D piezo-semiconductive NWs under purely vertical compressive or tensile strains. For simplicity, we exclusively consider the additional band bending originated by the piezoelectric charges assumed to be distributed, with a constant volumic density, within a maximum distance δpiezo 003F from the metal-to-NW junction. Our calculations demonstrate that the carrier concentration, the energy conduction band profile and the I-V characteristics significantly depend on δpiezo 003F . We therefore propose that I-V measurements can allow to obtain information on δpiezo 003F in strained piezo-semiconductors.

Dr. R. Araneo , Dr. G. Lovat DIAEE–Electrical Engineering Division “Sapienza” University of Rome Via Eudossiana 18, 00184, Rome, Italy Dr. P. Burghignoli Department of Information Engineering Electronics and Telecommunications “Sapienza” University of Rome Via Eudossiana 18, 00184, Rome, Italy Dr. C. alconi FDepartment of Electronic Engineering University of Tor Vergata Via del Politecnico 1, 00133, Rome, Italy E-mail: falconi@eln.uniroma2.it Dr. C. alconi F CNR IDASC Via Fosso del Cavaliere, 100, 00133 Rome, Italy

A procedure for the design of compact and lightweight absorbing material for damping resonances inside shielded enclosure is presented. The proposed absorber is based on the concept of the Jaumann layers and the circuit analog absorbers, since it employs four layers of lossy (artificial) dielectrics separated by two high/low impedance frequency selective surfaces and one resistive sheet. The constitutive parameters of the absorber are optimized by means of the Particle Swarm Optimization in order to maximize its bandwidth and absorption rate in the frequency range centered around 1 GHz, where the first resonances of small commercial enclosures take place.

Propagation features of the quasi-TEM mode supported by a graphene nano-ribbon placed on top of a grounded dielectric substrate are studied numerically with the Method of Moments in the spectral domain. A dyadic conductivity is adopted to model the graphene ribbon at microwave frequencies, taking into account the possible presence of static biasing fields and/or spatial-dispersion effects. Dispersion and attenuation properties are reported for typical values of the relevant physical parameters.

Propagation and attenuation properties of modes supported by graphene nano-ribbons placed on top of a grounded dielectric substrate are investigated by means of a spectral-domain Method-of-Moments approach together with a dyadic description of the graphene conductivity obtained based on semi-classical and quantum-mechanical arguments. Such a description takes into account the possible presence of static biasing fields or spatial-dispersion effects. The attenuation features are investigated and are compared to those of similar metal structures.

The electromagnetic effects of a nanostructured optically-transparent shield filling a thick aperture in shielding metallic enclosures with internal sources are investigated. The analysis is performed through an efficient Method-of-Moment technique and considers different shielding materials and source/aperture configurations; an effective numerical tool is thus offered for a fast determination of the best thin-film coating configurations. The investigation is also aimed at assessing the field distribution both inside and outside the metallic enclosure and at assessing whether the reduction of the electromagnetic field radiated outside the cavity in the presence of loaded apertures may determine dangerous effects on the interior components.

The paper investigates the EMI induced on electronic boards placed inside rectangular metallic enclosure having thin or thick apertures illuminated by a plane wave. The effects of optically-transparent thin films loading the apertures are also considered. The analysis is carried out through an integral-equation formulation which is able of dealing with micro/nano thin films. The investigation is aimed at assessing the level of the interference induced on the victim with open or loaded apertures.

The evaluation of the shielding effectiveness of metallic enclosures with apertures containing metallic objects and excited by arbitrary sources is the main topic of this work. The shielding effectiveness is computed through an integral formulation based on the Method of Moments which makes use of a fast computation of the enclosure Green functions. Absorbing artificial materials are also designed and proposed to damp the resonant fields excited inside the enclosure in order to improve the shielding performance.

This appendix contains sections titled: Magnetic Shielding Mechanism Calculation Methods Boundary-Value Problems Ferromagnetic Shields with Hysteresis References