Nature provides impressive examples of chiral photonic crystals, with the notable example cubic so-called srs network (the label for degree-three modeled on $\mathrm{SrS}{\mathrm{i}}_{2}$) or gyroid structure realized in wing scales several butterfly species. By a circular polarization analysis band such networks, we demonstrate strong dichroism effects: The microstructure, $I{4}_{1}32$ symmetry, shows significant blue to ultraviolet light, that warrants search biological receptors sensitive...

Abstract Optical metamaterials are artificially engineered architectures that exhibit desired optical properties not found in nature. Bespoke design requires the ability to define shape, size, orientation, and composition of material structures on nanometer length scale. Bottom‐up self‐assembly methods, such as block copolymer (BCP) templating, offer unique pathways tailored features, at spatial resolution routinely achieved by conventional top‐down techniques. In this review, authors...

The single Gyroid, a triply-periodic ordered chiral network of cubic symmetry, appears as nanostructure in the green-colored wing scales various butterflies. In lossless and perfectly Gyroid materials, structural chirality leads to circularly polarized reflections from crystals oriented [100] direction. Here we report circular polarisation study macroscopic Callophrys rubi Teinopalpus imperialis that reveals no dichroism, is, find significant difference reflectance values for left-...

Abstract Biopolymers offer vast potential for renewable and sustainable devices. While nature mastered the use of biopolymers to create highly complex 3D structures optimized their photonic response, artificially created still lack nature's diversity. To bridge this gap between natural engineered biophotonic structures, fundamental questions such as formation process interplay structural order disorder must be answered. Herein, biological characterization techniques are reviewed, focusing on...

Recent interest in optical analogs to the quantum spin Hall and valley effects is driven by promise establish topologically protected photonic edge modes at telecommunication wavelengths on a simple platform suitable for industrial applications. While first theoretical experimental efforts have been made, these approaches so far both lack rigorous understanding of nature topological protection limits backscattering immunity. We here use generic group methodology fill this gap obtain general...

Three-dimensional (3D) photonic structures enable numerous applications through their unique ability to guide, trap, and manipulate light. Constructing new functional crystals remains a significant challenge since traditional design principles based on band structure calculations require time-consuming computations. Additionally, is enumerated making it difficult find novel geometries. Here, we propose an ultra-fast crystal performance prediction method efficient optimization of arbitrary 3D...

Gold gyroid optical metamaterials are known to possess a reduced plasma frequency and linear dichroism imparted by their intricate subwavelength single morphology. The anisotropic properties are, however, only evident when large individual domain is investigated. Multidomain metamaterials, fabricated using polyisoprene-b-polystyrene-b-poly(ethylene oxide) triblock terpolymer consisting of multiple small domains with random orientation handedness, instead exhibit isotropic properties....

Over the past two decades, metamaterials have led to an increasing number of biosensing and nanophotonic applications due possibility a careful control light propagating through subwavelength features. Chiral nanostructures (characterized by absence any mirror symmetry), in particular, give rise unique chiro-optical properties such as circular dichroism optical activity. Here, we present gyroid metamaterial with periodicity 65 nm exhibiting strong at visible wavelengths. Our bottom-up...

For a number of optical applications, it is advantageous to precisely tune the refractive index liquid. Here, we harness well-established concept in optics for this purpose. The Kramers-Kronig relation provides physical connection between spectral variation (real) and absorption coefficient. In particular sharp coefficient gives rise either an enhancement or reduction vicinity variation. By using bright commodity dyes that fulfil requirement, demonstrate use predictively dial-in values water...

Plasmonic nanostructures can focus light far below the diffraction limit, and nearly thousandfold field enhancements obtained routinely enable few- single-molecule detection. However, for processes happening on molecular scale to be tracked with any relevant time resolution, emission strengths need well beyond what current plasmonic devices provide. Here, we develop hybrid incorporating both refractive optics, by creating SiO 2 nanospheres fused nanojunctions. Drastic improvements in Raman...

We use group or representation theory and scattering matrix calculations to derive analytical results for the band structure topology parameters, applicable any chiral photonic crystal with body-centered-cubic symmetry $I432$ circularly polarized incident light. demonstrate in particular that all bands along cubic $[100]$ direction can be identified irreducible representations ${E}_{\ifmmode\pm\else\textpm\fi{}}$, $A$, $B$ of ${C}_{4}$ point group. ${E}_{+}$ ${E}_{\ensuremath{-}}$ modes...

Classical topological phases derived from point degeneracies in photonic bandstructures show intriguing and unique behaviour. Previously identified exceptional points are based on accidental subject to engineering a case-by-case basis. Here we that symmetry induced (deterministic) pseudo Weyl with non-trivial topology hyper-conic dispersion exist at the centre of Brillouin zone chiral cubic systems. We establish physical implications by means $P2_13$ sphere packing, realised as nano...

Inverse bicontinuous cubic phases with two aqueous network domains separated by a smooth bilayer are firmly established as equilibrium in lipid/water systems. The purpose of this article is to highlight the generalisations these geometries polycontinuous geometries, which could be realised lipid mesophases three or more network-like branched bilayer. An analysis structural homogeneity terms width variations reveals that ordered likely candidates for mesophase structures, similar chain...

Abstract Optical metamaterials offer the tantalizing possibility of creating extraordinary optical properties through careful design and arrangement subwavelength structural units. Gyroid‐structured possess a chiral, cubic, triply periodic bulk morphology that exhibits redshifted effective plasma frequency. They also exhibit strong linear dichroism, origin which is not yet understood. Here, interaction light with gold gyroid studied correlation between surface its dichroism found. The...

Structural absorption is reported to be responsible for the deep black appearance of numerous living organisms, including butterflies, birds, and spiders. Here, we report presence structural in beetle Euprotaetia inexpectata, which has reflectivity values as low 0.1% absorptivity large 99.5%. By combining ultrastructural studies full-wave optical simulations, show that this generated by arrays anisotropic micropillars, enhance through a combination focusing Mie scattering. These results...

We propose a new approach to calculate the complex photonic band structure, both purely dispersive and evanescent Bloch modes of finite range, arbitrary three-dimensional crystals. Our method, based on well-established plane wave expansion weak form solution Maxwell’s equations, computes Fourier components periodic structures composed distinct homogeneous material domains from triangulated mesh representation inter-material interfaces; this allows substantially more accurate representations...

This paper shows that kagome lattices can be used for broadband and efficient unidirectional photonic edge mode propagation at sharp 120 degree bending. The authors propose a realistic device composed of an InGaAsP free-standing crystal working telecommunication wavelengths further show it has negligible vertical losses. Compared to conventional topological insulator designs, the simplicity kagome-lattice-based its all-dielectric nature make possible fabricate using many techniques.

Generation of amplified stimulated emission inside mammalian cells has paved the way for a novel bioimaging and cell sensing approach. Single carrying gain media (e.g., fluorescent molecules) are placed an optical cavity, allowing production intracellular laser upon sufficient pumping. Here, we investigate possibility to trigger another phenomenon (i.e., spontaneous or ASE) two different types, namely macrophage epithelial from species tissues, in presence poorly reflecting cavity....

Recent advances in the cataloguing of three-dimensional nets mean a systematic search for framework structures with specific properties is now feasible. Theoretical arguments about elastic deformation frameworks suggest characteristics mechanically isotropic networks. We explore these concepts on both and anisotropic networks by manufacturing porous elastomers three different periodic net geometries. The blocks patterned are subjected to range mechanical tests determine dependence moduli...

Hyperbolic metamaterials behave similarly to either metals or dielectrics depending on the polarization of incident light. This behavior is reflected in permittivity tensors having both negative and positive components, which leads interesting optics such as refraction super‐resolution imaging. To achieve this polarization‐dependent electromagnetic response, hyperbolic require a strongly anisotropic nanostructure made from noble metals. Herein, nanostructured array aligned gold silver...

We describe a new family of triply-periodic minimal surfaces with hexagonal symmetry, related to the quartz (qtz) and its dual (the qzd net). provide solution period problem parametrisation these surfaces, that are not in regular class, by Weierstrass-Enneper formalism. identified this analytical description surface generating an area-minimising mesh interface from pair graphs (qtz & qzd) using generalised Voronoi construction De Campo, Hyde colleagues, followed numerical identification...

A unidirectional chiral edge mode in photonic topological insulators can be selectively excited by a circularly-polarized dipole source. We show that the directionality is also determined position of

The circular dichroism (CD) of a material is the difference in optical absorption under left- and right-circularly polarized illumination. It crucial for number applications, from molecular sensing to design circularly thermal light sources. CD natural materials typically weak, leading exploitation artificial chiral materials. Layered woodpile structures are well known boost chiro-optical effects when realized as photonic crystal or an metamaterial. We here demonstrate that scattering at...