Resonant Transmission through Topological Metamaterial Grating

Abstract

Recently, artificial photonic structures that exhibit nontrivial topological properties have attracted growing attention due to their capability of achieving one-way backscatter immune transport of light. While photonic crystals are predominantly employed for achieving nontrivial topologies, effective medium approach based on metamaterials has been recently proposed for realizing topologically protected unidirectional surface states. In this article, a microscopic model to investigate the transmission of topological metamaterial grating is constructed based on the scattering processes involving unidirectional surface states. The numerically simulated transmission efficiency of the grating can be precisely reproduced by the model. The model demonstrates that the sharp transmission resonance of the grating results from the constructive interference of the topologically protected one-way surface states. The present work provides an intuitive picture for understanding the scattering processes and resonance behaviors of the topologically protected one-way surface states. Benefitting from the sharp spectral features of the supported resonances, the proposed grating structure may be potentially used for sensing applications.

Hyperbolic metamaterial using chiral molecules

“…Similarly, we can obtain the matrix elements of the interaction Hamiltonian under dipole approximation [37] H B = −m · B cos ωt (25) between the eigen-states of H which are written as Eqs. (10), (11). We also only give the matrix elements of intra-band transitions…”

“…Since it was theoretically proposed in 1968 [1], negative refraction has attracted broad interest because there is wide application for negative-index metamaterials [2][3][4][5][6][7][8][9][10][11][12], such as achieving electromagnetic-field cloaking [13,14], facilitating sub-wavelength imaging [2], and assisting crime scene investigation [15]. Various ways have been proposed to realize negative refraction.…”

Topologically Protected and Highly Localized Surface Waves in Gyro‐Electromagnetic Metamaterials

“…Liu The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/andp.202000022 DOI: 10.1002/andp.202000022 medium (hyperbolic chiral system) could result in photonic topological phases. [11,[26][27][28] Therefore, it has been widely concerned in the study of topological protected surface waves on this kind of metamaterials. [21,[29][30][31][32][33][34][35] The gyro-electromagnetic system simultaneously possesses nonzero gyrotropic elements in the permittivity and permeability tensors, which can bring a number of unique dispersion features.…”

“…That is quite different from the previous works where the nonreciprocal surface waves exist between open hyperbolic bulk states. [11,18,[26][27][28]…”

Optical pulling using topologically protected one way transport surface-arc waves

“…In 3D topological systems possessing Weyl nodes, the topological charges of Weyl points ensure the existence of chiral surface bands whose equifrequency sections form "Fermi arcs" (alternatively called surface arcs for general kinds of waves) that bridge the disconnected equifrequency surfaces (EFSs) of bulk states [31,32,34,[36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. Such chiral surface-arcs can exist in inversion-symmetry-broken systems respecting time-reversal symmetry [31,32].…”