English
Related papers

Related papers: Effective Medium Transformation: the Case of Strat…

200 papers

There is a growing mechanics literature concerning the macroscopic properties of mechanism-based mechanical metamaterials. This amounts mathematically to a homogenization problem involving nonlinear elasticity. A key goal is to identify the…

Analysis of PDEs · Mathematics 2025-11-10 Xuenan Li , Robert V. Kohn

In a homogeneous medium, the far-field generated by a localized source can be expanded in terms of multipoles; the coefficients are determined by the moments of the localized charge distribution. We show that this structure survives to some…

Analysis of PDEs · Mathematics 2017-08-28 Peter Bella , Arianna Giunti , Felix Otto

The impact of granular microstructure in permanent magnets on eddy current losses are investigated. A numerical homogenization procedure for electrical conductivity is defined. Then, an approximated simple analytical model for the…

Applied Physics · Physics 2020-06-02 Salvatore Perna , Thomas Schrefl , Claudio Serpico , Johann Fischbacher , Andrea Del Pizzo

By modeling a dielectric medium with two independent reservoirs, i.e., electric and magnetic reservoirs, the electromagnetic field is quantized in a linear dielectric medium consistently. A Hamiltonian is proposed from which using the…

Quantum Physics · Physics 2007-05-23 F. Kheirandish , M. Amooshahi

Compressible magnetohydrodynamic (MHD) turbulence is ubiquitous in astrophysical phenomena ranging from the intergalactic to the stellar scales. In studying them, numerical simulations are nearly inescapable, due to the large degree of…

Fluid Dynamics · Physics 2016-07-27 Dimitar G Vlaykov , Philipp Grete , Wolfram Schmidt , Dominik R G Schleicher

Periodic structures can be engineered to exhibit unique properties observed at symmetry points, such as zero group velocity, Dirac cones and saddle points; identifying these, and the nature of the associated modes, from a direct reading of…

Here, we present an overview of a first principles homogenization theory of periodic metamaterials. It is shown that in a rather general context it is possible to formally introduce effective parameters that describe the time evolution of…

Optics · Physics 2020-02-18 Sylvain Lannebère , Tiago A. Morgado , Mário G. Silveirinha

A physically consistent approach is considered for defining an external magnetic field as needed in computational fluid dynamics problems involving magnetohydrodynamics (MHD). The approach results in simple analytical formulae that can be…

Fluid Dynamics · Physics 2009-11-25 E. V. Votyakov , S. C. Kassinos , X. Albets-Chico

It is well-known under the name of `periodic homogenization' that, under a centering condition of the drift, a periodic diffusion process on R^d converges, under diffusive rescaling, to a d-dimensional Brownian motion. Existing proofs of…

Probability · Mathematics 2014-09-22 Martin Hairer , Etienne Pardoux

A major challenge in flow through porous media is to better understand the link between microstructure and macroscale flow and transport. For idealised microstructures, the mathematical framework of homogenisation theory can be used for…

We study the homogenization of a stationary conductivity problem in a random heterogeneous medium with highly oscillating conductivity coefficients and an ensemble of simply closed conductivity resistant membranes. This medium is randomly…

Analysis of PDEs · Mathematics 2015-06-02 Wenjia Jing

Classical theory of crystals states that a medium to be considered homogeneous must satisfy the following requirements: a) the dimension of the elementary cell must be much smaller than the incident wavelength; b) the sample must contain a…

An effective medium theory for resonant and non-resonant metamaterials for flexural waves in thin plates is presented. The theory provides closed-form expressions for the effective parameters of arrangement of inclusions or resonators in…

Materials Science · Physics 2014-10-08 Daniel Torrent , Yan Pennec , Bahram Djafari-Rouhani

By modeling a linear polarizable and magnetizable medium (magneto-dielectric) with two quantum fields, namely E and M, electromagnetic field is quantized in such a medium consistently and systematically. A Hamiltonian is proposed from…

Quantum Physics · Physics 2009-11-11 F. Kheirandish , A. Amooshahi

The approach to calculating the effective dielectric and magnetic response in bounded composite materials is developed. The method is essentially based on the renormalisation of the dielectric matrix parameters to account for the surface…

Materials Science · Physics 2009-11-07 D. P. Makhnovskiy , L. V. Panina , D. J. Mapps , A. K. Sarychev

We introduce a homogenization approach to characterize the dynamical response of a generic dispersive spacetime crystal in the long-wavelength limit. The theory is applied to dispersive spacetime platforms with a travelling-wave modulation.…

Optics · Physics 2023-07-26 João C. Serra , Mário G. Silveirinha

We present an effective medium description of time-modulated dielectric media. By taking the averaged fields over one modulation period, the relationship between them is derived, defining therefore the different constitutive parameters. In…

Optics · Physics 2021-01-04 Dani Torrent

Anisotropic homogeneous metamaterials that are neither wholly dissipative nor wholly active at a specific frequency are permitted by classical electromagnetic theory. Well-established homogenization formalisms indicate that such a…

Optics · Physics 2015-12-22 Tom G. Mackay , Akhlesh Lakhtakia

We investigate a homogenization problem for a linearly elastic magnetic material that incorporates elastically rigid magnetic inclusions firmly bonded to the matrix. By considering a periodic arrangement of this material, we identify an…

Analysis of PDEs · Mathematics 2025-06-24 Raffaele Grande , Stefan Krömer , Martin Kružík , Giuseppe Tomassetti

In the work, a modified effective medium theory is constructed for calculating the effective properties of thermoelectric composites with different values of percolation thresholds. It is shown that even at concentrations beyond the…

Materials Science · Physics 2020-06-23 Snarskii Andrei , Yuskevich Pavel