English
Related papers

Related papers: Effective medium theories for irregular fluffy str…

200 papers

Observations of interstellar extinction and polarization indicate that the interstellar medium consists of aligned non-spherical dust grains which show variation in the interstellar extinction curve for wavelengths ranging from NIR to UV.…

Astrophysics · Physics 2009-09-15 Ranjan Gupta , Tadashi Mukai , D. B. Vaidya , Asoke K. Sen , Yasuhiko Okada

We consider a system of particles undergoing correlated diffusion with elastic boundary conditions on the half-line. By taking the large particle limit we establish existence and uniqueness for the limiting empirical measure valued process…

Probability · Mathematics 2022-10-19 Ben Hambly , Julian Meier , Andreas Sojmark

This paper focuses on the time-harmonic electromagnetic (EM) scattering problem in a general medium which may possess a nontrivial topological structure. We model this by an inhomogeneous and possibly anisotropic medium with embedded…

Analysis of PDEs · Mathematics 2024-08-14 Huaian Diao , Hongyu Liu , Qingle Meng , Li Wang

We derive the effective medium theory for the linearized time-domain acoustic waves propagating in a bubbly media. The analysis is done in the time-domain avoiding the need to use Fourier transformation. This allows considering general…

Analysis of PDEs · Mathematics 2024-08-05 Arpan Mukherjee , Mourad Sini

Using the method of separation of variables and a new approach to calculations of the prolate spheroidal wave functions, we study the optical properties of very elongated (cigar-like) spheroidal particles. A comparison of extinction…

Astrophysics · Physics 2009-11-07 N V Voshchinnikov , V G Farafonov

Nonlocal coordinate space optical potentials for the scattering of 65 MeV protons from nuclei ranging in mass from 6Li to 238U have been defined by folding a complex, medium dependent effective interaction with the density matrix elements…

Nuclear Theory · Physics 2008-11-26 P. J. Dortmans , K. Amos , S. Karataglidis , J. Raynal

This work presents theoretical and numerical models for the backscattering of two-dimensional Rayleigh waves by an elastic inclusion, with the host material being isotropic and the inclusion having arbitrary shape and crystallographic…

Classical Physics · Physics 2023-04-27 Shan Li , Ming Huang , Yongfeng Song , Bo Lan , Xiongbing Li

Current effective medium theories for nano-shells are reviewed. A new method for calculating the effective dielectric function of a core-shell nanoparticle is presented and compared with existing theories showing clear advantages in most…

Correctly modelling the absorptive properties of dust and haze particles is of great importance for determining the abundance of solid matter within protoplanetary disks and planetary atmospheres. Rigorous analyses such as the discrete…

Earth and Planetary Astrophysics · Physics 2024-10-30 M. G. Lodge , H. R. Wakeford , Z. M. Leinhardt

We present an effective medium theory that can predict the effective permittivity and permeability of a geometrically anisotropic two-dimensional metamaterial composed with a rectangular array of elliptical cylinders. It is possible to…

Optics · Physics 2016-11-10 Xiujuan Zhang , Ying Wu

We provide a general microscopic theory of the scattering cross-section and of the refractive index for a system of interacting colloidal particles, exact at second order in the molecular polarizabilities. In particular: a) we show that the…

Soft Condensed Matter · Physics 2014-10-01 Alberto Parola , Roberto Piazza , Vittorio Degiorgio

$Context.$ The quantification of the terahertz (THz) and IR optical properties of astrophysical ice analogs, which have different molecular compositions, phases, and structural properties, is required to model both the continuum emission by…

Instrumentation and Methods for Astrophysics · Physics 2025-08-29 A. A. Gavdush , A. V. Ivlev , K. I. Zaytsev , V. E. Ulitko , I. N. Dolganova , S. V. Garnov , B. M. Giuliano , P. Caselli

Unique and highly tunable optical properties of PT-symmetric systems and metamaterials enable a plenty of entirely new linear and nonlinear optical phenomena with numerous applications, e.g., for designing subdiffraction lenses,…

Optics · Physics 2019-04-15 Denis Novitsky , Alexander Shalin , Andrey Novitsky

Two different formalisms for the homogenization of composite materials containing ellipsoidal inclusions based on Bruggeman's original formula for spherical inclusions can be found in the literature. Both approximations determine the…

Optics · Physics 2013-09-13 Daniel Schmidt , Mathias Schubert

We use a new approach to derive dielectric mixing rules for macroscopically homogeneous and isotropic multicomponent mixtures of anisotropic inhomogeneous dielectric particles. Two factors of anisotropy are taken into account, the shape of…

Materials Science · Physics 2015-05-13 M. Ya. Sushko

Context. Dust grains coagulate to form dust aggregates in protoplanetary disks. Their porosity can be extremely high in the disks. Although disk emission may come from fluffy dust aggregates, the emission has been modeled with compact…

Earth and Planetary Astrophysics · Physics 2014-09-05 Akimasa Kataoka , Satoshi Okuzumi , Hidekazu Tanaka , Hideko Nomura

Periodic photonic lattices constitute a fundamental pillar of physics supporting a plethora of scientific concepts and applications. The advent of metamaterials and metastructures is grounded in deep understanding of their properties. Based…

Optics · Physics 2020-06-11 Hafez Hemmati , Robert Magnusson

Effective medium theory aims to describe a complex inhomogeneous material in terms of a few important macroscopic parameters. To characterise wave propagation through an inhomogeneous material, the most crucial parameter is the effective…

Classical Physics · Physics 2019-08-13 Artur Lewis Gower , Ian David Abrahams , William J. Parnell

We perform light-scattering numerical simulations for two dust populations: (i) consolidated porous particles computed with the discrete dipole approximation (ADDA) and (ii) highly porous aggregate models, including fractal and hierarchical…

We present a multiple-scattering model for the effective refractive index of an arbitrarily dense suspension of forward-scattering particles. The model provides a very simple formula for the effective refractive index of such a suspension…

Optics · Physics 2023-08-02 Alexander Nahmad-Rohen , Augusto García-Valenzuela