Polarizability Tensor Retrieval for Subwavelength Particles of Arbitrary Shape

Liu, Xingxiang; Zhao, Yang; Alù, Andrea

doi:10.1109/tap.2016.2546958

Cited by 32 publications

(50 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In metamaterials and metaphotonics, manipulation of light at the nanoscale utilizes optically resonant subwavelength meta-atoms, whose properties have generally been analyzed by dipolar α-tensor [40][41][42]. However, recently emerged high-refractive-index particles [5,8,27,28,49] and coupled plasmonic systems [17,43] often involve higher-order multipole transitions.…”

Section: Meta-atoms and Metaphotonicsmentioning

confidence: 99%

“…The broad ED resonance is easily attributed to (α e1 e1 ) x x , and the sharp EQ and MD resonances are spectrally attributed to (α m1 m1 ) z z , (α e2 e2 ) xy xy , and (α m1 e2 ) z xy . Analysis from α-tensor allows us to see that PDB has different origin of optical magnetism from splitring resonators [40,42] and high-refractive-index spheres (see Appendix F for more details). Importantly, only a few components are dominant in the retrieved α-tensor, making the analysis easier ( Fig.…”

Section: Meta-atoms and Metaphotonicsmentioning

confidence: 99%

See 1 more Smart Citation

Describing Meta-Atoms Using the Exact Higher-Order Polarizability Tensors

Mun

Jang

et al. 2020

ACS Photonics

View full text Add to dashboard Cite

In nanophotonics, multipole approach has become an indispensable theoretical framework for analyzing subwavelength meta-atoms and their radiation properties. Thus far, induced multipole moments have frequently used to illustrate the radiating properties of the meta-atoms, but they are excited at a specific illumination and do not fully represent anisotropic meta-atoms. On the other hand, dynamic polarizability (α) tensors contain complete scattering information of the metaatoms, but have not often been considered due to complicated retrieval procedures. In this study, we suggest that exact higher-order α-tensor can be efficiently obtained from T-matrix using simple basis transformation. These higher-order α-tensors are necessary to describe recently reported coupled plasmonic and high-refractive-index particles, which we demonstrate from their retrieved α-tensors. Finally, we show that description of meta-atoms using α-tensors incorporated with multiple-scattering theory vastly extends the applicability of the multipole approach in nanophotonics, allowing accurate and efficient depiction of complicated, random, multi-scale systems. Usage: Preprint.

show abstract

Section: Meta-atoms and Metaphotonicsmentioning

confidence: 99%

Section: Meta-atoms and Metaphotonicsmentioning

confidence: 99%

Describing Meta-Atoms Using the Exact Higher-Order Polarizability Tensors

Mun

Jang

et al. 2020

ACS Photonics

View full text Add to dashboard Cite

show abstract

“…Using the polarization extraction technique to be presented, a metamaterial element is reduced to an effective electric dipole moment and an effective magnetic dipole moment, p and m, which are proportional to the local electric or magnetic field at the center of the element multiplied by a coupling coefficient, termed the dynamic polarizability [77]. It is referred to as "dynamic" since it describes the element's response due to a time-varying incident field.…”

Section: Self-consistent Dipole Model For Metasurfacesmentioning

confidence: 99%

Polarizability extraction of complementary metamaterial elements in waveguides for aperture modeling

et al. 2017

View full text Add to dashboard Cite

We consider the design and modeling of metasurfaces that couple energy from guided waves to propagating wavefronts. This is a first step towards a comprehensive, multiscale modeling platform for metasurface antennas-large arrays of metamaterial elements embedded in a waveguide structure that radiates intro free-space-in which the detailed electromagnetic responses of metamaterial elements are replaced by polarizable dipoles. We present two methods to extract the effective polarizability of a metamaterial element embedded in a one-or two-dimensional waveguide. The first method invokes surface equivalence principles, averaging over the effective surface currents and charges within an element to obtain the effective dipole moments; the second method is based on computing the coefficients of the scattered waves within the waveguide, from which the effective polarizability can be inferred. We demonstrate these methods on several variants of waveguidefed metasurface elements, finding excellent agreement between the two, as well as with analytical expressions derived for irises with simpler geometries. Extending the polarizability extraction technique to higher order multipoles, we confirm the validity of the dipole approximation for common metamaterial elements. With the effective polarizabilities of the metamaterial elements accurately determined, the radiated fields generated by a metasurface antenna (inside and outside the antenna) can be found self-consistently by including the interactions between polarizable dipoles. The dipole description provides an alternative language and computational framework for engineering metasurface antennas, holograms, lenses, beam-forming arrays, and other electrically large, waveguide-fed metasurface structures.

show abstract

“…The interaction between pressure and velocity fields makes the scattering problem more complicated, while also presents novel wavefront manipulation possibilities that conventional metasurfaces do not have. [22][23][24][25][26][27] For example, Koo et al 28 took advantage of the pressure-velocity coupling to achieve simultaneous control of transmitted and reflected wavefronts. Li et al 29 proposed a systematic design approach to improve the efficiency of acoustic metasurfaces using bianisotropic unit cells.…”

Section: Introductionmentioning

confidence: 99%

Retrieval method for the bianisotropic polarizability tensor of Willis acoustic scatterers

Norris

2018

Phys. Rev. B

View full text Add to dashboard Cite

Acoustic materials displaying coupling between pressure and momentum are known as Willis materials. The simplest Willis materials are comprised of sub-wavelength scatterers that couple monopoles to dipoles and vice versa, with the interaction defined by a polarizability tensor. We propose a method for retrieving the polarizability tensor for sub-wavelength Willis acoustic scatterers using a finite set of scattering amplitudes. We relate the polarizability tensor to standard T-matrix and S-matrix scattering formalisms. This leads to an explicit method for retrieving the components of the polarizability tensor in terms of a small set of scattered pressure data in the near-or far-field. Numerical examples demonstrate the retrieval method for one and two dimensional configurations.

show abstract

Polarizability Tensor Retrieval for Subwavelength Particles of Arbitrary Shape

Cited by 32 publications

References 30 publications

Describing Meta-Atoms Using the Exact Higher-Order Polarizability Tensors

Describing Meta-Atoms Using the Exact Higher-Order Polarizability Tensors

Polarizability extraction of complementary metamaterial elements in waveguides for aperture modeling

Retrieval method for the bianisotropic polarizability tensor of Willis acoustic scatterers

Contact Info

Product

Resources

About