Brewster quasi bound states in the continuum in all-dielectric metasurfaces from single magnetic-dipole resonance meta-atoms

Abujetas, Diego R.; Barreda, Ángela; Moreno, Fernando; Sáenz, Juan José; Litman, Amélie; Geffrin, Jean-Michel; Sánchez‐Gil, José A.

doi:10.1038/s41598-019-52223-4

Cited by 34 publications

(61 citation statements)

References 54 publications

(62 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This has been shown with high‐refractive‐index (HRI), all‐dielectric meta‐atoms (disks o pillars) exhibiting either electric dipole resonances in the visible [ 8 ] or magnetic dipole resonances in the GHz. [ 32,33 ] The latter indeed showed how a canonical isolated BIC emerges from a single, non‐degenerate magnetic‐dipole resonance, thanks to the fact that this is the lowest‐order (non‐overlapping) resonance of the high‐refractive‐index disk meta‐atoms used therein. On the other hand, recall the classical analogue of quantum electromagnetically‐induced transparency (EIT) has been widely explored in metasurfaces, where the three level system needed is typically replaced by mode coupling of two resonances of various kinds.…”

Section: Introductionmentioning

confidence: 91%

“…First of all, let us recall the magnetic‐dipole (MD) resonances that the disks to be used in the experimental measurements exhibit. [ 32 ] If we assume a nearly dispersionless dielectric permittivity

ε = 78 + 0.05 i

, disks can be simply defined in terms of their aspect ratio, diameter/height=

D / L = 1.5

. The analysis can be thus generalized to most of the electromagnetic spectrum, since there are various materials that possess such dielectric constant at diverse spectral regions from the IR to the microwave regimes.…”

Section: Lattice‐induced Tuning Of MD Bicmentioning

confidence: 99%

“…Therefore, let us calculate the reflection spectra from an infinite array for varying angle of incidence θ through our CEMD in such a case: recall that, for

D / a = 0.5

, both MD resonances do not overlap and the MD

_{⊥}

gives rise to a symmetry‐protected (Brewster‐like) BIC as revealed experimentally for

a = 12

mm in the microwave regime. [ 32 ] The resulting reflection intensity and phase are shown in Figure a,b for

D / a \approx 0.75

. Near normal incidence, a broad reflection band is observed, with a narrow dip of negligible reflection splitting it, in turn tending to vanish at

ω a / (2 π c) \approx 0.16

.…”

Section: Quasi‐bic‐induced Transparency Bandmentioning

confidence: 99%

“…Focusing on the normal incidence band of interest, we observe in Figure 2c that the MD

_{⊥}

exhibits the characteristic behavior of a symmetry‐protected BIC: namely, a narrowing resonant band with diverging Q‐factor that disappears at normal incidence (Γ point). The symmetry protection allowing BIC emergence was explained in terms of a Brewster‐like mechanism, [ 32 ] forbidding excitation/emission of a perpendicular dipole (either electric or magnetic) at normal incidence, otherwise the only available direction at the Γ point imposed by the periodicity of the metasurface. However, the other MD

_{false| false|}

resonance exhibits a broad band around normal incidence (see Figure 2e) due to the fact that coupling in (and scattering from) such dipolar resonance (with in‐plane electric and magnetic fields) is fully permitted.…”

Section: Quasi‐bic‐induced Transparency Bandmentioning

confidence: 99%

See 3 more Smart Citations

High‐Q Transparency Band in All‐Dielectric Metasurfaces Induced by a Quasi Bound State in the Continuum

Abujetas

Barreda

Moreno

et al. 2020

Laser & Photonics Reviews

Self Cite

View full text Add to dashboard Cite

Bound states in the continuum (BICs) emerge throughout physics as leaky/resonant modes that remain, however, highly localized. They have attracted much attention in optics and photonics, and especially in metasurfaces, that is, planar arrays of sub‐wavelength meta‐atoms. One of their most outstanding features is the arbitrarily large Q‐factors they induce upon approaching the BIC condition, which is exploited here to achieve a narrow transparency band. It is first shown how to shift a canonical BIC in an all‐dielectric metasurface, consisting of high‐refractive disks exhibiting in‐ and out‐of‐plane magnetic dipole (MD) resonances, by tuning the periodicity of the array. By means of the coupled electric/magnetic dipole formulation, it is shown analytically that when the quasi‐BIC overlaps with the broad (in‐plane MD) resonance, a full transparency band emerges with diverging Q‐factor upon approaching the BIC condition in parameter space. Finally, the experimental measurements in the microwave regime with a large array of high‐refractive‐index disks confirm the theoretical predictions. The results reveal a simple mechanism to engineer an ultra‐narrow BIC‐induced transparency band that can be exploited throughout the electromagnetic spectrum with obvious applications in filtering and sensing.

show abstract

Section: Introductionmentioning

confidence: 91%

ε = 78 + 0.05 i

, disks can be simply defined in terms of their aspect ratio, diameter/height=

D / L = 1.5

Section: Lattice‐induced Tuning Of MD Bicmentioning

confidence: 99%

“…Therefore, let us calculate the reflection spectra from an infinite array for varying angle of incidence θ through our CEMD in such a case: recall that, for

D / a = 0.5

, both MD resonances do not overlap and the MD

_{⊥}

gives rise to a symmetry‐protected (Brewster‐like) BIC as revealed experimentally for

a = 12

mm in the microwave regime. [ 32 ] The resulting reflection intensity and phase are shown in Figure a,b for

D / a \approx 0.75

. Near normal incidence, a broad reflection band is observed, with a narrow dip of negligible reflection splitting it, in turn tending to vanish at

ω a / (2 π c) \approx 0.16

.…”

Section: Quasi‐bic‐induced Transparency Bandmentioning

confidence: 99%

“…Focusing on the normal incidence band of interest, we observe in Figure 2c that the MD

_{⊥}

_{false| false|}

Section: Quasi‐bic‐induced Transparency Bandmentioning

confidence: 99%

See 2 more Smart Citations

High‐Q Transparency Band in All‐Dielectric Metasurfaces Induced by a Quasi Bound State in the Continuum

Abujetas

Barreda

Moreno

et al. 2020

Laser & Photonics Reviews

Self Cite

View full text Add to dashboard Cite

show abstract

“…Recent achievements in the field of BIC are discussed in Refs. [17][18][19][20][21][22][23][24][25][26].…”

Section: Introductionmentioning

confidence: 99%

Multipolar origin of bound states in the continuum

et al. 2019

View full text Add to dashboard Cite

Metasurfaces based on resonant subwavelength photonic structures enable novel ways of wavefront control and light focusing, underpinning a new generation of flat-optics devices. Recently emerged all-dielectric metasurfaces exhibit high-quality resonances underpinned by the physics of bound states in the continuum that drives many interesting concepts in photonics. Here we suggest a novel approach to explain the physics of bound photonic states embedded into the radiation continuum. We study dielectric metasurfaces composed of planar periodic arrays of Mie-resonant nanoparticles ("meta-atoms") which support both symmetry protected and accidental bound states in the continuum, and employ the multipole decomposition approach to reveal the physical mechanism of the formation of such nonradiating states in terms of multipolar modes generated by isolated meta-atoms. Based on the symmetry of the vector spherical harmonics, we identify the conditions for the existence of bound states in the continuum originating from the symmetries of both the lattice and the unit cell. Using this formalism we predict that metasurfaces with strongly suppressed spatial dispersion can support the bound states in the continuum with the wavevectors forming a line in the reciprocal space. Our results provide a new way for designing high-quality resonant photonic systems based on the physics of bound states in the continuum.

show abstract

Resonant Dual‐Grating Metamembranes Supporting Spectrally Narrow Bound States in the Continuum

Hemmati

Magnusson

2019

Advanced Optical Materials

View full text Add to dashboard Cite

second-order Bragg condition was satisfied. Later, in 1979, Vincent and Neviere numerically demonstrated the existence of a nonleaky edge pertinent to symmetric grating designs while introducing asymmetry to the grating profile resulted in leaky radiating modes at both band edges. [4] Ding and Magnusson manipulated the separation of the nondegenerate leaky resonances associated with asymmetric profiles to engineer the resonant spectral response of periodic films. [5] Experimentally, the nonleaky edge, and thus BIC, was revealed in 1998 by imposing asymmetry on an otherwise symmetric periodic structure by variation in the angle of incidence. [6] Thus, optical BICs are grounded in confined (nonleaky) modes with an infinite lifetime above the light line in the dispersion diagram of periodic structures. Well established symmetry-protected BICs with exact zero resonance bandwidth (true BIC) reside at the Γ point of the band diagram based on the symmetry incompatibility between the asymmetric standing waves inside the structure and symmetric outgoing waves. [7][8][9][10][11][12] In addition, it has been shown both theoretically and experimentally that off-Γ BIC, with nearzero resonance linewidth (quasi-BIC or asymptotic BIC) can be obtained at specific incident angles in periodic structures. [13][14][15] Moreover, quasi-BICs at the Γ point were reported for specific physical parameters of nanostructures. [16] These nearly zero resonance linewidths possess quasiembedded eigenvalues which cause coupling to the radiated waves.Whereas there have been extensive studies conducted on metamaterial devices with a single spatial periodicity, [17][18][19][20][21][22][23] there is less research on resonance elements containing multiple spatial periodic layers. Unquestionably, there are additional design dimensions to be exploited with such architectures as any multiperiodic construct will operate on available bound modes differently than a single periodicity. Thus, there are scientific and practical reasons to explore attendant device designs and corresponding spectral response. Past related work includes demonstration that properly designed dually corrugated waveguides support unidirectional output radiation. [24] Similar elements were advanced as solutions to improve the efficiency and stability of second-order surface emitting laser diodes via substrate radiation suppression. [24,25] In 2014, a unidirectional coupler for surface plasmon polaritons was proposed and Properties of photonic devices fashioned with dual-grating metamaterials are reported. Enclosed by dual periodic regions, laterally propagating Bloch modes undergo radiative scattering and leaky-mode resonance whose properties differ markedly from those with single periodicity. The resonance signatures are sensitively controlled by the relative parameters of the periodic regions. In particular, if they are physically identical and separated by a half-wavelength, there ensues a bound state in the continuum (BIC) with extremely narrow resonance linewidth. On varying the...

show abstract

Brewster quasi bound states in the continuum in all-dielectric metasurfaces from single magnetic-dipole resonance meta-atoms

Cited by 34 publications

References 54 publications

High‐Q Transparency Band in All‐Dielectric Metasurfaces Induced by a Quasi Bound State in the Continuum

High‐Q Transparency Band in All‐Dielectric Metasurfaces Induced by a Quasi Bound State in the Continuum

Multipolar origin of bound states in the continuum

Resonant Dual‐Grating Metamembranes Supporting Spectrally Narrow Bound States in the Continuum

Contact Info

Product

Resources

About