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Recent intense interest in nanoparticle materials and nanoparticle-based contrast enhancement agents for biophysical applications gives new relevance to Mie scattering theory in its original context of application. The Mie theory still provides the most exact treatment of scattering from single nanoparticles of the noble metals. When recast in terms of modern electrodynamic formalism, the theory provides a concise closed-form representation for the scattered fields and also serves as a vehicle to elaborate the formal electrodynamic technique. The behavior of the Debye truncation condition for the multipole expansion is illustrated with numerical examples, clearly showing the features of the transition between the Rayleigh, dipole and higher order multipole approximations for the scattered fields. The classical Mie theory is an approximation in that only the transverse field components are included in the calculation. Extensions to the classical theory which include the effects of longitudinal fields are discussed and illustrated numerically. The example of scattering from multilayer composite particles is used to examine the feasibility of engineering spectral features of the scattering cross-section to target the requirements of specific applications.

Ag/Co nanoparticles (NPs) were prepared by a two-step method. First, Ag NPs were synthesized by "Controlled Current Coulometry" (CCC) electrochemical method using a Pt rotating electrode. Then, Ag/Co core-shell NPs were prepared through the reduction method using Ag NPs as a core. Both steps were accomplished at room temperature. Techniques such as patterned X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed for the characterization of Ag/Co NPs. Optical properties of synthesized NPs were also investigated by UV-Vis spectroscopy. The absorption peak of Ag NPs was observed at ~400 nm wavelength and the peaks that were detected at 425 nm and 415 nm wavelengths reveal the formation of Ag/Co NPs. The core-shell structure of Ag/Co NPs was confirmed by thermal and electrochemical techniques. We also applied "Mie" theory to calculate the absorption cross-section band of synthesized Ag/Co NPs. Comparison between the results of optical properties and also those obtained from "Mie" theory showed good agreements.

We present a simple method to prove the presence of an organic shell around silver nanoparticles (NPs). This method is based on the comparison between optical extinction measurements of isolated NPs and Mie calculations predicting the expected wavelength of the Localized Surface Plasmon Resonance of the NPs with and without the presence of an organic layer. This method was applied to silver NPs which seemed to be well protected from oxidation. Further experimental characterization via surface enhanced raman spectroscopy (SERS) measurements allowed to identify this protective shell as ethylene glycol. Combining LSPR and SERS measurements could thus give proof of both presence and identification for other plasmonic NPs surrounded by organic shells.

Near-infrared spectroscopy (NIRS) technology and Mie theory are utilized for fundamental research on radiofrequency ablation of biological tissue. Firstly, NIRS is utilized to monitor rats undergoing radiofrequency ablation surgery in real time so as to explore the relationship between reduced scattering coefficient () and the degree of thermally induced tissue coagulation. Then, Mie theory is utilized to analyze the morphological structure change of biological tissue so as to explore the basic mechanism of the change of optical parameters caused by thermally induced tissue coagulation. Results show that there is a close relationship between and the degree of thermally induced tissue coagulation; the degree of thermal coagulation can be obtained by the value of ; when biological tissue thermally coagulates, the average equivalent scattering particle decreases, the particle density increases, and the anisotropy factor decreases.

Frequency selective surface (FSS) has been extensively studied due to its potential applications in radomes, antenna reflectors, high-impedance surfaces and absorbers. Recently, a new principle of designing FSS has been proposed and mainly studied in two levels. In the level of materials, dielectric materials instead of metallic patterns are capable of achieving more functional performance in FSS design. Moreover, FSSs made of dielectric materials can be used in different extreme environments, depending on their electrical, thermal or mechanical properties. In the level of design principle, the theory of metamaterial can be used to design FSS in a convenient and concise way. In this review paper, we provide a brief summary about the recent progress in all-dielectric metamaterial frequency selective surface (ADM-FSS). The basic principle of designing ADM-FSS is summarized. As significant tools, Mie theory and dielectric resonator (DR) theory are given which illustrate clearly how they are used in the FSS design. Then, several design cases including dielectric particle-based ADM-FSS and dielectric network-based ADM-FSS are introduced and reviewed. After a discussion of these two types of ADM-FSSs, we reviewed the existing fabrication techniques that are used in building the experiment samples. Finally, issues and challenges regarding the rapid fabrication techniques and further development aspects are discussed.

Graphite flakes are excluded as a major component of interstellar grains because their ultraviolet extinction peaks occur at wavelengths longward of 2700 Å. Mie calculations for spherical graphite particles are shown to have no physical or astronomical relevance.

Scattering of electromagnetic waves on a single particle is a basic microcosmic physical process for cloud research. The Mie theory was used to get the measurement of scattering sphere particles. In order to eliminate the RCS (Radar Cross-Section) fluctuation of sphere target, MIMO (Multiple Input Multiple Output) radar technique was adopted to get multi-angle backscattering values. The simulation results show that MIMO radar can improve the backscattering intensity, which is better for cloud target inversion. Different size of particles was also simulated to compare the single radar and MIMO radar: with the increasing of particle scale, the backscattering gradually decreases.