A hollow spherical non-closed-packed face-centered cubic uniaxial structure with a photonic band gap

ABSTRACTA level set approach was used to study photonic band gaps for dielectric composites with symmetries of the eleven face centered cubic lattices. Candidate structures were modeled for each group by a 3D surface given by f(x,y,z)-t=0 obtained by equating f to an appropriate sum of structure factor terms. This approach allows us to easily map different structures and gives us an insight into the effects of symmetry, connectivity and genus on photonic band gaps. It is seen that a basic set of symmetries defines the essential band gap and connectivity. The remaining symmetry elements modify the band gap. The eleven lattices are classified into four fundamental topologies on the basis of the occupancy of high symmetry Wyckoff sites. Of the fundamental topologies studied, three display band gaps--- including two: the (F-RD) and a group 216 structure that have not been reported previously.

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THE SIZE INFLUENCE OF SILICA MICROSPHERES ON PHOTONIC BAND GAP OF PHOTONIC CRYSTALS

International Journal of Modern Physics B ◽

10.1142/s0217979207037338 ◽

2007 ◽

Vol 21 (16) ◽

pp. 2761-2768 ◽

Cited By ~ 2

Author(s):

XIYING MA ◽

ZHIJUN YAN

Keyword(s):

Photonic Crystals ◽

Band Gap ◽

Photonic Band Gap ◽

Three Dimensional ◽

Refraction Index ◽

Face Centered Cubic ◽

Silica Microspheres ◽

Large Shift ◽

Face Centered ◽

Photonic Band

The size influence of silica microspheres on the photonic band gap (PBG) of three-dimensional face-centered-cubic (fcc) photonic crystals (PCs) is studied by means of colloidal photonic crystals, which are self-assembled by the vertical deposition technique. Monodispersed SiO 2 microspheres with a diameter of 220–320 nm are synthesized using tetraethylorthosilicate (TEOS) as a precursor material. We find that the PBG of the PCs shifts from 450 nm to 680 nm with silica spheres increasing from 220 to 320 nm. In addition, the PBG moves to higher photon energy when the samples are annealed in a temperature range of 200–700°C. The large shift results from the decrease in refraction index of silica due to moisture evaporation.

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Fabrication and Optical Properties of Nb2O5 Inverse Opal Photonic Crystals by PS Opal Template

Materials Science Forum ◽

10.4028/www.scientific.net/msf.688.90 ◽

2011 ◽

Vol 688 ◽

pp. 90-94 ◽

Cited By ~ 1

Author(s):

Y.Q. Yang ◽

P.D. Han ◽

Y.P. Li ◽

M.H. Dong ◽

L.L. Zhang ◽

...

Keyword(s):

Band Gap ◽

Photonic Band Gap ◽

Face Centered Cubic ◽

Inverse Opal ◽

Void Space ◽

Inverse Opal Structure ◽

Calculation Results ◽

Face Centered ◽

Vertical Deposition Method ◽

Photonic Band

In this paper, polystyrene (PS) opals template, opal with a closed-packed face centered cubic (fcc) lattice, was prepared using vertical deposition method. The template provided void space for infiltration of Nb2O5 etc. PS colloidal nanospheres was face-centered-cubic (FCC) structure with its (111) planes parallel to the substrate. Finally, the transfer matrix method (TMM) was used to calculate photonic band-gap of PS opal and Nb2O5 inverse opal structure. The calculation results show that the photonic band-gap of Nb2O5 with inverse opal structure is wider than that of PS opals.

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Simulations of Realizable Photonic Bandgap Structures with High Refractive Contrast

MRS Proceedings ◽

10.1557/proc-694-k5.6 ◽

2001 ◽

Vol 694 ◽

Author(s):

Bonnie Gersten ◽

Jennifer Synowczynski

Keyword(s):

Periodic Structures ◽

Photonic Band Gap ◽

Three Dimensional ◽

Face Centered Cubic ◽

High Permittivity ◽

Face Centered ◽

Photonic Bandgap Structures ◽

Photonic Band ◽

Opal Crystal ◽

Periodic Arrangement

AbstractThe transfer matrix method (TMM) software (Translight, A. Reynolds [1]) was used to evaluate the photonic band gap (PBG) properties of the periodic arrangement of high permittivity ferroelectric composite (40 wt% Ba0.45Sr0.55TiO3 /60 wt% MgO composite, εR= 80, tanδ = 0.0041 at 10 GHz) in air (or Styrofoam, εR~ 1) matrix compared to a lower permittivity material (Al2O3, εR= 11.54, tanδ = 0.00003 at 10 GHz) in air. The periodic structures investigated included a one-dimensional (1D) stack and a three-dimensional (3D) face centered cubic (FCC) opal structure. The transmission spectrum was calculated for the normalized frequency for all incident angles for each structure. The results show that the bandgaps frequency increased and the bandgap width increased with increased permittivity. The effects of orientation of defects in the opal crystal were investigated. It was found by introducing defects propagation bands were introduced. It was concluded that a full PBG is possible with the high permittivity material.

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Simulations of Realizable Photonic Bandgap Structures with High Refractive Contrast

MRS Proceedings ◽

10.1557/proc-692-k5.6.1 ◽

2001 ◽

Vol 692 ◽

Author(s):

Bonnie Gersten ◽

Jennifer Synowczynski

Keyword(s):

Periodic Structures ◽

Photonic Band Gap ◽

Three Dimensional ◽

Face Centered Cubic ◽

High Permittivity ◽

Face Centered ◽

Photonic Bandgap Structures ◽

Photonic Band ◽

Opal Crystal ◽

Periodic Arrangement

AbstractThe transfer matrix method (TMM) software (Translight, A. Reynolds [1]) was used to evaluate the photonic band gap (PBG) properties of the periodic arrangement of high permittivity ferroelectric composite (40 wt% Ba0.45Sr0.55TiO3/60 wt% MgO composite, εR = 80, tanδ?= 0.0041 at 10 GHz) in air (or Styrofoam, εR ∼ 1) matrix compared to a lower permittivity material (Al2O3, εR = 11.54, tanδ?= 0.00003 at 10 GHz) in air. The periodic structures investigated included a one-dimensional (1D) stack and a three-dimensional (3D) face centered cubic (FCC) opal structure. The transmission spectrum was calculated for the normalized frequency for all incident angles for each structure. The results show that the bandgaps frequency increased and the bandgap width increased with increased permittivity. The effects of orientation of defects in the opal crystal were investigated. It was found by introducing defects propagation bands were introduced. It was concluded that a full PBG is possible with the high permittivity material.

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Synthesis and Study of the Optical Properties of PMMA Microspheres and Opals

Polymers ◽

10.3390/polym13132171 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2171

Author(s):

Mayra Matamoros-Ambrocio ◽

Enrique Sánchez-Mora ◽

Estela Gómez-Barojas ◽

José Alberto Luna-López

Keyword(s):

Band Gap ◽

Self Assembly ◽

Photonic Band Gap ◽

Average Diameter ◽

Reflectance Spectra ◽

Face Centered Cubic ◽

Indirect Transition ◽

Specular Reflectance ◽

Assembly Method ◽

Face Centered

Polymethylmethacrylate (PMMA) microspheres were synthesized by surfactant-free emulsion polymerization. These microspheres were used to obtain opals by the self-assembly method. Monomer and initiator quantities were varied systematically to monitor the size of PMMA microspheres. From SEM and DLS measurements, a trend was observed showing as the monomer and initiator amounts increased the average diameter of PMMA microspheres increased except when a minimum monomer amount was reached, for which the size of the microspheres remained practically constant. Diffuse reflectance spectra were processed by the Kubelka–Munk treatment to estimate the energy band gap (Eg) of the PMMA microspheres. It was found that PMMA microspheres present an indirect transition. From SEM micrographs, it is seen that PMMA opals photonic crystals are formed by microspheres in a uniform periodic face-centered cubic (fcc) array. Variable-angle specular reflectance spectra show that the opals possess a pseudo photonic band gap (PBG) in the visible and near-IR regions. Furthermore, it was found that PBGs shift towards larger wavelengths as the average diameter of the PMMA microspheres increases.

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